switch to using boost::signals2 instead of sigc++, at least for libardour. not finished yet, but compiles, loads sessions, records and can close a session without a crash

git-svn-id: svn://localhost/ardour2/branches/3.0@6372 d708f5d6-7413-0410-9779-e7cbd77b26cf

352 files changed, 3491 insertions, 3544 deletions

diff --git a/gtk2_ardour/add_route_dialog.cc b/gtk2_ardour/add_route_dialog.cc
index a828caeb92..a3d3deaea5 100644
--- a/gtk2_ardour/add_route_dialog.cc
+++ b/gtk2_ardour/add_route_dialog.cc
@@ -61,13 +61,14 @@ std::vector<std::string> AddRouteDialog::channel_combo_strings;
 std::vector<std::string> AddRouteDialog::track_mode_strings;
 std::vector<std::string> AddRouteDialog::bus_mode_strings;
 
-AddRouteDialog::AddRouteDialog (Session & s)
+AddRouteDialog::AddRouteDialog (Session* s)
 	: ArdourDialog (X_("add route dialog"))
-	, _session (s)
 	, routes_adjustment (1, 1, 128, 1, 4)
 	, routes_spinner (routes_adjustment)
 	, mode_label (_("Track mode:"))
 {
+	set_session (s);
+
 	if (track_mode_strings.empty()) {
 		track_mode_strings = I18N (track_mode_names);
 
@@ -391,7 +392,7 @@ AddRouteDialog::route_group ()
 		return 0;
 	}
 
-	return _session.route_group_by_name (route_group_combo.get_active_text());
+	return _session->route_group_by_name (route_group_combo.get_active_text());
 }
 
 void
@@ -404,7 +405,7 @@ AddRouteDialog::refill_route_groups ()
 
 	route_group_combo.append_text (_("No group"));
 
-	_session.foreach_route_group (sigc::mem_fun (*this, &AddRouteDialog::add_route_group));
+	_session->foreach_route_group (sigc::mem_fun (*this, &AddRouteDialog::add_route_group));
 
 	route_group_combo.set_active (2);
 }
@@ -412,14 +413,14 @@ AddRouteDialog::refill_route_groups ()
 void
 AddRouteDialog::group_changed ()
 {
-	if (route_group_combo.get_active_text () == _("New group...")) {
-		RouteGroup* g = new RouteGroup (_session, "", RouteGroup::Active);
+	if (_session && route_group_combo.get_active_text () == _("New group...")) {
+		RouteGroup* g = new RouteGroup (*_session, "", RouteGroup::Active);
 
 		RouteGroupDialog d (g, Gtk::Stock::NEW);
 		int const r = d.do_run ();
 
 		if (r == Gtk::RESPONSE_OK) {
-			_session.add_route_group (g);
+			_session->add_route_group (g);
 			add_route_group (g);
 			route_group_combo.set_active (3);
 		} else {
diff --git a/gtk2_ardour/add_route_dialog.h b/gtk2_ardour/add_route_dialog.h
index 7af8b47d8d..1422270331 100644
--- a/gtk2_ardour/add_route_dialog.h
+++ b/gtk2_ardour/add_route_dialog.h
@@ -42,7 +42,7 @@ class Editor;
 class AddRouteDialog : public ArdourDialog
 {
   public:
-	AddRouteDialog (ARDOUR::Session &);
+	AddRouteDialog (ARDOUR::Session*);
 	~AddRouteDialog ();
 
 	bool track ();
@@ -58,7 +58,6 @@ class AddRouteDialog : public ArdourDialog
 	ARDOUR::RouteGroup* route_group ();
 
   private:
-	ARDOUR::Session& _session;
 	Gtk::Entry name_template_entry;
 	Gtk::ComboBoxText track_bus_combo;
 	Gtk::Adjustment routes_adjustment;
diff --git a/gtk2_ardour/analysis_window.cc b/gtk2_ardour/analysis_window.cc
index c916678646..6d858732ff 100644
--- a/gtk2_ardour/analysis_window.cc
+++ b/gtk2_ardour/analysis_window.cc
@@ -250,7 +250,7 @@ AnalysisWindow::analyze_data (Gtk::Button */*button*/)
 		Sample *mixbuf = (Sample *) malloc(sizeof(Sample) * fft_graph.windowSize());
 		float  *gain   = (float *)  malloc(sizeof(float) * fft_graph.windowSize());
 
-		Selection s = PublicEditor::instance().get_selection();
+		Selection& s (PublicEditor::instance().get_selection());
 		TimeSelection ts = s.time;
 		RegionSelection ars = s.regions;
 
diff --git a/gtk2_ardour/analysis_window.h b/gtk2_ardour/analysis_window.h
index 05b983fb20..19ef84069a 100644
--- a/gtk2_ardour/analysis_window.h
+++ b/gtk2_ardour/analysis_window.h
@@ -37,6 +37,8 @@
 
 #include <glibmm/thread.h>
 
+#include "ardour/session_handle.h"
+
 #include "fft_graph.h"
 #include "fft_result.h"
 
@@ -44,7 +46,8 @@ namespace ARDOUR {
 	class Session;
 }
 
-class AnalysisWindow : public Gtk::Window
+
+class AnalysisWindow : public Gtk::Window, public ARDOUR::SessionHandlePtr
 {
 public:
 	AnalysisWindow  ();
@@ -57,12 +60,7 @@ public:
 
 	void analyze ();
 
-	void set_session(ARDOUR::Session *session) { _session = session; };
-
 private:
-
-	ARDOUR::Session *_session;
-
 	void clear_tracklist();
 
 	void source_selection_changed (Gtk::RadioButton *);
diff --git a/gtk2_ardour/ardour_dialog.cc b/gtk2_ardour/ardour_dialog.cc
index cafb356d60..cd95666b16 100644
--- a/gtk2_ardour/ardour_dialog.cc
+++ b/gtk2_ardour/ardour_dialog.cc
@@ -90,7 +90,6 @@ ArdourDialog::on_show ()
 void
 ArdourDialog::init ()
 {
-	session = 0;
 	set_type_hint(Gdk::WINDOW_TYPE_HINT_DIALOG);
 	set_border_width (10);
 	CloseAllDialogs.connect (sigc::bind (sigc::mem_fun (*this, &ArdourDialog::response), RESPONSE_CANCEL));
diff --git a/gtk2_ardour/ardour_dialog.h b/gtk2_ardour/ardour_dialog.h
index cd0fce4162..bd74afc47d 100644
--- a/gtk2_ardour/ardour_dialog.h
+++ b/gtk2_ardour/ardour_dialog.h
@@ -20,20 +20,23 @@
 #ifndef __ardour_dialog_h__
 #define __ardour_dialog_h__
 
-#include "ardour/ardour.h"
 #include <gtkmm/window.h>
 #include <gtkmm/dialog.h>
 
+#include "ardour/ardour.h"
+#include "ardour/session_handle.h"
+
 namespace ARDOUR {
 	class Session;
 }
 
 /*
  * This virtual parent class is so that each dialog box uses the
- * same mechanism to declare its closing, and to have a common
- * method of connecting and disconnecting from a Session.
+ * same mechanism to declare its closing. It shares a common
+ * method of connecting and disconnecting from a Session with
+ * all other objects that have a handle on a Session.
  */
-class ArdourDialog : public Gtk::Dialog
+class ArdourDialog : public Gtk::Dialog, public ARDOUR::SessionHandlePtr
 {
   public:
 	ArdourDialog (std::string title, bool modal = false, bool use_separator = false);
@@ -48,16 +51,6 @@ class ArdourDialog : public Gtk::Dialog
 	void on_unmap ();
 	void on_show ();
 
-	ARDOUR::Session *session;
-
-	virtual void set_session (ARDOUR::Session* s) {
-		session = s;
-	}
-
-	virtual void session_gone () {
-		set_session (0);
-	}
-
 	static void close_all_dialogs () { CloseAllDialogs(); }
 
   private:
diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index 9086bde940..f97d892c4c 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -193,7 +193,6 @@ ARDOUR_UI::ARDOUR_UI (int *argcp, char **argvp[])
 
 	editor = 0;
 	mixer = 0;
-	session = 0;
 	editor = 0;
 	engine = 0;
 	_session_is_new = false;
@@ -415,11 +414,11 @@ ARDOUR_UI::post_engine ()
 	/* now start and maybe save state */
 
 	if (do_engine_start () == 0) {
-		if (session && _session_is_new) {
+		if (_session && _session_is_new) {
 			/* we need to retain initial visual
 			   settings for a new session
 			*/
-			session->save_state ("");
+			_session->save_state ("");
 		}
 	}
 }
@@ -556,9 +555,9 @@ ARDOUR_UI::save_ardour_state ()
 	XMLNode enode(static_cast<Stateful*>(editor)->get_state());
 	XMLNode mnode(mixer->get_state());
 
-	if (session) {
-		session->add_instant_xml (enode);
-		session->add_instant_xml (mnode);
+	if (_session) {
+		_session->add_instant_xml (enode);
+		_session->add_instant_xml (mnode);
 	} else {
 		Config->add_instant_xml (enode);
 		Config->add_instant_xml (mnode);
@@ -582,8 +581,8 @@ ARDOUR_UI::autosave_session ()
                 return 1;
 	}
 
-        if (session) {
-                session->maybe_write_autosave();
+        if (_session) {
+                _session->maybe_write_autosave();
         }
 
 	return 1;
@@ -594,7 +593,7 @@ ARDOUR_UI::update_autosave ()
 {
 	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::update_autosave)
 
-	if (session && session->dirty()) {
+	if (_session && _session->dirty()) {
 		if (_autosave_connection.connected()) {
 			_autosave_connection.disconnect();
 		}
@@ -753,14 +752,14 @@ ARDOUR_UI::check_memory_locking ()
 void
 ARDOUR_UI::finish()
 {
-	if (session) {
+	if (_session) {
 
-		if (session->transport_rolling()) {
-			session->request_stop ();
+		if (_session->transport_rolling()) {
+			_session->request_stop ();
 			usleep (250000);
 		}
 
-		if (session->dirty()) {
+		if (_session->dirty()) {
 			switch (ask_about_saving_session(_("quit"))) {
 			case -1:
 				return;
@@ -789,10 +788,10 @@ If you still wish to quit, please use the\n\n\
 		point_oh_five_second_connection.disconnect ();
 		point_zero_one_second_connection.disconnect();
 		
-		// session->set_deletion_in_progress ();
-		session->remove_pending_capture_state ();
-		delete session;
-		session = 0;
+		// _session->set_deletion_in_progress ();
+		_session->remove_pending_capture_state ();
+		delete _session;
+		_session = 0;
 	}
 
 	ArdourDialog::close_all_dialogs ();
@@ -826,13 +825,13 @@ ARDOUR_UI::ask_about_saving_session (const string & what)
 	string prompt;
 	string type;
 
-	if (session->snap_name() == session->name()) {
+	if (_session->snap_name() == _session->name()) {
 		type = _("session");
 	} else {
 		type = _("snapshot");
 	}
 	prompt = string_compose(_("The %1 \"%2\"\nhas not been saved.\n\nAny changes made this time\nwill be lost unless you save it.\n\nWhat do you want to do?"),
-			 type, session->snap_name());
+			 type, _session->snap_name());
 
 	prompt_label.set_text (prompt);
 	prompt_label.set_name (X_("PrompterLabel"));
@@ -941,14 +940,14 @@ ARDOUR_UI::update_buffer_load ()
 	char buf[64];
 	uint32_t c, p;
 
-	if (session) {
-		c = session->capture_load ();
-		p = session->playback_load ();
+	if (_session) {
+		c = _session->capture_load ();
+		p = _session->playback_load ();
 
 		push_buffer_stats (c, p);
 
 		snprintf (buf, sizeof (buf), _("Buffers p:%" PRIu32 "%% c:%" PRIu32 "%%"),
-			  session->playback_load(), session->capture_load());
+			  _session->playback_load(), _session->capture_load());
 		buffer_load_label.set_text (buf);
 	} else {
 		buffer_load_label.set_text ("");
@@ -967,19 +966,19 @@ ARDOUR_UI::count_recenabled_streams (Route& route)
 void
 ARDOUR_UI::update_disk_space()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	nframes_t frames = session->available_capture_duration();
+	nframes_t frames = _session->available_capture_duration();
 	char buf[64];
-	nframes_t fr = session->frame_rate();
+	nframes_t fr = _session->frame_rate();
 
 	if (frames == max_frames) {
 		strcpy (buf, _("Disk: 24hrs+"));
 	} else {
 		rec_enabled_streams = 0;
-		session->foreach_route (this, &ARDOUR_UI::count_recenabled_streams);
+		_session->foreach_route (this, &ARDOUR_UI::count_recenabled_streams);
 
 		if (rec_enabled_streams) {
 			frames /= rec_enabled_streams;
@@ -1154,7 +1153,7 @@ ARDOUR_UI::recent_session_row_activated (const TreePath& /*path*/, TreeViewColum
 void
 ARDOUR_UI::open_recent_session ()
 {
-	bool can_return = (session != 0);
+	bool can_return = (_session != 0);
 
 	if (session_selector_window == 0) {
 		build_session_selector ();
@@ -1278,7 +1277,7 @@ ARDOUR_UI::session_add_midi_route (bool disk, RouteGroup* route_group, uint32_t
 {
 	list<boost::shared_ptr<MidiTrack> > tracks;
 
-	if (session == 0) {
+	if (_session == 0) {
 		warning << _("You cannot add a track without a session already loaded.") << endmsg;
 		return;
 	}
@@ -1286,7 +1285,7 @@ ARDOUR_UI::session_add_midi_route (bool disk, RouteGroup* route_group, uint32_t
 	try {
 		if (disk) {
 
-			tracks = session->new_midi_track (ARDOUR::Normal, route_group, how_many);
+			tracks = _session->new_midi_track (ARDOUR::Normal, route_group, how_many);
 
 			if (tracks.size() != how_many) {
 				if (how_many == 1) {
@@ -1296,7 +1295,7 @@ ARDOUR_UI::session_add_midi_route (bool disk, RouteGroup* route_group, uint32_t
 				}
 			}
 		} /*else {
-			if ((route = session->new_midi_route ()) == 0) {
+			if ((route = _session->new_midi_route ()) == 0) {
 				error << _("could not create new midi bus") << endmsg;
 			}
 		}*/
@@ -1319,14 +1318,14 @@ ARDOUR_UI::session_add_audio_route (bool track, bool aux, int32_t input_channels
 	list<boost::shared_ptr<AudioTrack> > tracks;
 	RouteList routes;
 
-	if (session == 0) {
+	if (_session == 0) {
 		warning << _("You cannot add a track or bus without a session already loaded.") << endmsg;
 		return;
 	}
 
 	try {
 		if (track) {
-			tracks = session->new_audio_track (input_channels, output_channels, mode, route_group, how_many);
+			tracks = _session->new_audio_track (input_channels, output_channels, mode, route_group, how_many);
 
 			if (tracks.size() != how_many) {
 				if (how_many == 1) {
@@ -1339,7 +1338,7 @@ ARDOUR_UI::session_add_audio_route (bool track, bool aux, int32_t input_channels
 
 		} else {
 
-			routes = session->new_audio_route (aux, input_channels, output_channels, route_group, how_many);
+			routes = _session->new_audio_route (aux, input_channels, output_channels, route_group, how_many);
 
 			if (routes.size() != how_many) {
 				if (how_many == 1) {
@@ -1379,9 +1378,9 @@ ARDOUR_UI::do_transport_locate (nframes_t new_position)
 {
 	nframes_t _preroll = 0;
 
-	if (session) {
+	if (_session) {
 		// XXX CONFIG_CHANGE FIX - requires AnyTime handling
-		// _preroll = session->convert_to_frames_at (new_position, Config->get_preroll());
+		// _preroll = _session->convert_to_frames_at (new_position, Config->get_preroll());
 
 		if (new_position > _preroll) {
 			new_position -= _preroll;
@@ -1389,22 +1388,22 @@ ARDOUR_UI::do_transport_locate (nframes_t new_position)
 			new_position = 0;
 		}
 
-		session->request_locate (new_position);
+		_session->request_locate (new_position);
 	}
 }
 
 void
 ARDOUR_UI::transport_goto_start ()
 {
-	if (session) {
-		session->goto_start();
+	if (_session) {
+		_session->goto_start();
 
 		/* force displayed area in editor to start no matter
 		   what "follow playhead" setting is.
 		*/
 
 		if (editor) {
-			editor->center_screen (session->current_start_frame ());
+			editor->center_screen (_session->current_start_frame ());
 		}
 	}
 }
@@ -1412,8 +1411,8 @@ ARDOUR_UI::transport_goto_start ()
 void
 ARDOUR_UI::transport_goto_zero ()
 {
-	if (session) {
-		session->request_locate (0);
+	if (_session) {
+		_session->request_locate (0);
 
 
 		/* force displayed area in editor to start no matter
@@ -1429,7 +1428,7 @@ ARDOUR_UI::transport_goto_zero ()
 void
 ARDOUR_UI::transport_goto_wallclock ()
 {
-	if (session && editor) {
+	if (_session && editor) {
 
 		time_t now;
 		struct tm tmnow;
@@ -1438,11 +1437,11 @@ ARDOUR_UI::transport_goto_wallclock ()
 		time (&now);
 		localtime_r (&now, &tmnow);
 
-		frames = tmnow.tm_hour * (60 * 60 * session->frame_rate());
-		frames += tmnow.tm_min * (60 * session->frame_rate());
-		frames += tmnow.tm_sec * session->frame_rate();
+		frames = tmnow.tm_hour * (60 * 60 * _session->frame_rate());
+		frames += tmnow.tm_min * (60 * _session->frame_rate());
+		frames += tmnow.tm_sec * _session->frame_rate();
 
-		session->request_locate (frames);
+		_session->request_locate (frames);
 
 		/* force displayed area in editor to start no matter
 		   what "follow playhead" setting is.
@@ -1457,9 +1456,9 @@ ARDOUR_UI::transport_goto_wallclock ()
 void
 ARDOUR_UI::transport_goto_end ()
 {
-	if (session) {
-		nframes_t const frame = session->current_end_frame();
-		session->request_locate (frame);
+	if (_session) {
+		nframes_t const frame = _session->current_end_frame();
+		_session->request_locate (frame);
 
 		/* force displayed area in editor to start no matter
 		   what "follow playhead" setting is.
@@ -1474,23 +1473,23 @@ ARDOUR_UI::transport_goto_end ()
 void
 ARDOUR_UI::transport_stop ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	if (session->is_auditioning()) {
-		session->cancel_audition ();
+	if (_session->is_auditioning()) {
+		_session->cancel_audition ();
 		return;
 	}
 
-	session->request_stop ();
+	_session->request_stop ();
 }
 
 void
 ARDOUR_UI::transport_stop_and_forget_capture ()
 {
-	if (session) {
-		session->request_stop (true);
+	if (_session) {
+		_session->request_stop (true);
 	}
 }
 
@@ -1506,47 +1505,47 @@ void
 ARDOUR_UI::transport_record (bool roll)
 {
 
-	if (session) {
-		switch (session->record_status()) {
+	if (_session) {
+		switch (_session->record_status()) {
 		case Session::Disabled:
-			if (session->ntracks() == 0) {
+			if (_session->ntracks() == 0) {
 				MessageDialog msg (*editor, _("Please create 1 or more track\nbefore trying to record.\nCheck the Session menu."));
 				msg.run ();
 				return;
 			}
-			session->maybe_enable_record ();
+			_session->maybe_enable_record ();
 			if (roll) {
 				transport_roll ();
 			}
 			break;
 		case Session::Recording:
 			if (roll) {
-				session->request_stop();
+				_session->request_stop();
 			} else {
-				session->disable_record (false, true);
+				_session->disable_record (false, true);
 			}
 			break;
 
 		case Session::Enabled:
-			session->disable_record (false, true);
+			_session->disable_record (false, true);
 		}
 	}
-	//cerr << "ARDOUR_UI::transport_record () called roll = " << roll << " session->record_status() = " << session->record_status() << endl;
+	//cerr << "ARDOUR_UI::transport_record () called roll = " << roll << " _session->record_status() = " << _session->record_status() << endl;
 }
 
 void 
 ARDOUR_UI::transport_roll ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	if (session->is_auditioning()) {
+	if (_session->is_auditioning()) {
 		return;
 	}
 	
-	if (session->config.get_external_sync()) {
-		switch (session->config.get_sync_source()) {
+	if (_session->config.get_external_sync()) {
+		switch (_session->config.get_sync_source()) {
 		case JACK:
 			break;
 		default:
@@ -1555,16 +1554,16 @@ ARDOUR_UI::transport_roll ()
 		}
 	}
 
-	bool rolling = session->transport_rolling();
+	bool rolling = _session->transport_rolling();
 
-	if (session->get_play_loop()) {
-		session->request_play_loop (false, true);
-	} else if (session->get_play_range ()) {
-		session->request_play_range (false, true);
+	if (_session->get_play_loop()) {
+		_session->request_play_loop (false, true);
+	} else if (_session->get_play_range ()) {
+		_session->request_play_range (false, true);
 	} 
 
 	if (!rolling) {
-		session->request_transport_speed (1.0f);
+		_session->request_transport_speed (1.0f);
 	}
 
 	map_transport_state ();
@@ -1574,17 +1573,17 @@ void
 ARDOUR_UI::toggle_roll (bool with_abort, bool roll_out_of_bounded_mode)
 {
 	
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	if (session->is_auditioning()) {
-		session->cancel_audition ();
+	if (_session->is_auditioning()) {
+		_session->cancel_audition ();
 		return;
 	}
 	
-	if (session->config.get_external_sync()) {
-		switch (session->config.get_sync_source()) {
+	if (_session->config.get_external_sync()) {
+		switch (_session->config.get_sync_source()) {
 		case JACK:
 			break;
 		default:
@@ -1593,12 +1592,12 @@ ARDOUR_UI::toggle_roll (bool with_abort, bool roll_out_of_bounded_mode)
 		}
 	}
 
-	bool rolling = session->transport_rolling();
+	bool rolling = _session->transport_rolling();
 	bool affect_transport = true;
 
 	if (rolling && roll_out_of_bounded_mode) {
 		/* drop out of loop/range playback but leave transport rolling */
-		if (session->get_play_loop()) {
+		if (_session->get_play_loop()) {
 			if (Config->get_seamless_loop()) {
 				/* the disk buffers contain copies of the loop - we can't 
 				   just keep playing, so stop the transport. the user
@@ -1609,18 +1608,18 @@ ARDOUR_UI::toggle_roll (bool with_abort, bool roll_out_of_bounded_mode)
 				/* disk buffers are normal, so we can keep playing */
 				affect_transport = false;
 			}
-			session->request_play_loop (false, true);
-		} else if (session->get_play_range ()) {
+			_session->request_play_loop (false, true);
+		} else if (_session->get_play_range ()) {
 			affect_transport = false;
-			session->request_play_range (0, true);
+			_session->request_play_range (0, true);
 		} 
 	} 
 
 	if (affect_transport) {
 		if (rolling) {
-			session->request_stop (with_abort, true);
+			_session->request_stop (with_abort, true);
 		} else {
-			session->request_transport_speed (1.0f);
+			_session->request_transport_speed (1.0f);
 		}
 	}
 
@@ -1630,20 +1629,20 @@ ARDOUR_UI::toggle_roll (bool with_abort, bool roll_out_of_bounded_mode)
 void
 ARDOUR_UI::toggle_session_auto_loop ()
 {
-	if (session) {
-		if (session->get_play_loop()) {
-			if (session->transport_rolling()) {
-				Location * looploc = session->locations()->auto_loop_location();
+	if (_session) {
+		if (_session->get_play_loop()) {
+			if (_session->transport_rolling()) {
+				Location * looploc = _session->locations()->auto_loop_location();
 				if (looploc) {
-					session->request_locate (looploc->start(), true);
+					_session->request_locate (looploc->start(), true);
 				}
 			} else {
-				session->request_play_loop (false);
+				_session->request_play_loop (false);
 			}
 		} else {
-			Location * looploc = session->locations()->auto_loop_location();
+			Location * looploc = _session->locations()->auto_loop_location();
 			if (looploc) {
-				session->request_play_loop (true);
+				_session->request_play_loop (true);
 			}
 		}
 	}
@@ -1652,7 +1651,7 @@ ARDOUR_UI::toggle_session_auto_loop ()
 void
 ARDOUR_UI::transport_play_selection ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -1664,24 +1663,24 @@ ARDOUR_UI::transport_rewind (int option)
 {
 	float current_transport_speed;
 
-       	if (session) {
-		current_transport_speed = session->transport_speed();
+       	if (_session) {
+		current_transport_speed = _session->transport_speed();
 
 		if (current_transport_speed >= 0.0f) {
 			switch (option) {
 			case 0:
-				session->request_transport_speed (-1.0f);
+				_session->request_transport_speed (-1.0f);
 				break;
 			case 1:
-				session->request_transport_speed (-4.0f);
+				_session->request_transport_speed (-4.0f);
 				break;
 			case -1:
-				session->request_transport_speed (-0.5f);
+				_session->request_transport_speed (-0.5f);
 				break;
 			}
 		} else {
 			/* speed up */
-			session->request_transport_speed (current_transport_speed * 1.5f);
+			_session->request_transport_speed (current_transport_speed * 1.5f);
 		}
 	}
 }
@@ -1691,24 +1690,24 @@ ARDOUR_UI::transport_forward (int option)
 {
 	float current_transport_speed;
 
-	if (session) {
-		current_transport_speed = session->transport_speed();
+	if (_session) {
+		current_transport_speed = _session->transport_speed();
 
 		if (current_transport_speed <= 0.0f) {
 			switch (option) {
 			case 0:
-				session->request_transport_speed (1.0f);
+				_session->request_transport_speed (1.0f);
 				break;
 			case 1:
-				session->request_transport_speed (4.0f);
+				_session->request_transport_speed (4.0f);
 				break;
 			case -1:
-				session->request_transport_speed (0.5f);
+				_session->request_transport_speed (0.5f);
 				break;
 			}
 		} else {
 			/* speed up */
-			session->request_transport_speed (current_transport_speed * 1.5f);
+			_session->request_transport_speed (current_transport_speed * 1.5f);
 		}
 
 	}
@@ -1717,13 +1716,13 @@ ARDOUR_UI::transport_forward (int option)
 void
 ARDOUR_UI::toggle_record_enable (uint32_t dstream)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
 	boost::shared_ptr<Route> r;
 
-	if ((r = session->route_by_remote_id (dstream)) != 0) {
+	if ((r = _session->route_by_remote_id (dstream)) != 0) {
 
 		Track* t;
 
@@ -1731,7 +1730,7 @@ ARDOUR_UI::toggle_record_enable (uint32_t dstream)
 			t->diskstream()->set_record_enabled (!t->diskstream()->record_enabled());
 		}
 	}
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 }
@@ -1741,7 +1740,7 @@ ARDOUR_UI::map_transport_state ()
 {
 	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::map_transport_state)
 
-	if (!session) {
+	if (!_session) {
 		auto_loop_button.set_visual_state (0);
 		play_selection_button.set_visual_state (0);
 		roll_button.set_visual_state (0);
@@ -1749,7 +1748,7 @@ ARDOUR_UI::map_transport_state ()
 		return;
 	}
 
-	float sp = session->transport_speed();
+	float sp = _session->transport_speed();
 
 	if (sp == 1.0f) {
 		shuttle_fract = SHUTTLE_FRACT_SPEED1;  /* speed = 1.0, believe it or not */
@@ -1762,13 +1761,13 @@ ARDOUR_UI::map_transport_state ()
 
 	if (sp != 0.0) {
 
-		if (session->get_play_range()) {
+		if (_session->get_play_range()) {
 
 			play_selection_button.set_visual_state (1);
 			roll_button.set_visual_state (0);
 			auto_loop_button.set_visual_state (0);
 			
-		} else if (session->get_play_loop ()) {
+		} else if (_session->get_play_loop ()) {
 			
 			auto_loop_button.set_visual_state (1);
 			play_selection_button.set_visual_state (0);
@@ -1900,7 +1899,7 @@ void
 ARDOUR_UI::update_clocks ()
 {
 	if (!editor || !editor->dragging_playhead()) {
-		Clock (session->audible_frame(), false, editor->get_preferred_edit_position()); /* EMIT_SIGNAL */
+		Clock (_session->audible_frame(), false, editor->get_preferred_edit_position()); /* EMIT_SIGNAL */
 	}
 }
 
@@ -1994,7 +1993,7 @@ ARDOUR_UI::snapshot_session ()
 		bool do_save = (snapname.length() != 0);
 
 		vector<sys::path> p;
-		get_state_files_in_directory (session->session_directory().root_path(), p);
+		get_state_files_in_directory (_session->session_directory().root_path(), p);
 		vector<string> n = get_file_names_no_extension (p);
 		if (find (n.begin(), n.end(), snapname) != n.end()) {
 
@@ -2030,14 +2029,14 @@ ARDOUR_UI::save_state (const string & name)
 int
 ARDOUR_UI::save_state_canfail (string name)
 {
-	if (session) {
+	if (_session) {
 		int ret;
 
 		if (name.length() == 0) {
-			name = session->snap_name();
+			name = _session->snap_name();
 		}
 
-		if ((ret = session->save_state (name)) != 0) {
+		if ((ret = _session->save_state (name)) != 0) {
 			return ret;
 		}
 	}
@@ -2048,36 +2047,36 @@ ARDOUR_UI::save_state_canfail (string name)
 void
 ARDOUR_UI::primary_clock_value_changed ()
 {
-	if (session) {
-		session->request_locate (primary_clock.current_time ());
+	if (_session) {
+		_session->request_locate (primary_clock.current_time ());
 	}
 }
 
 void
 ARDOUR_UI::big_clock_value_changed ()
 {
-	if (session) {
-		session->request_locate (big_clock.current_time ());
+	if (_session) {
+		_session->request_locate (big_clock.current_time ());
 	}
 }
 
 void
 ARDOUR_UI::secondary_clock_value_changed ()
 {
-	if (session) {
-		session->request_locate (secondary_clock.current_time ());
+	if (_session) {
+		_session->request_locate (secondary_clock.current_time ());
 	}
 }
 
 void
 ARDOUR_UI::transport_rec_enable_blink (bool onoff)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	Session::RecordState const r = session->record_status ();
-	bool const h = session->have_rec_enabled_diskstream ();
+	Session::RecordState const r = _session->record_status ();
+	bool const h = _session->have_rec_enabled_diskstream ();
 
 	if (r == Session::Enabled || (r == Session::Recording && !h)) {
 		if (onoff) {
@@ -2105,7 +2104,7 @@ ARDOUR_UI::save_template ()
 	prompter.set_name (X_("Prompter"));
 	prompter.set_title (_("Save Mix Template"));
 	prompter.set_prompt (_("Name for mix template:"));
-	prompter.set_initial_text(session->name() + _("-template"));
+	prompter.set_initial_text(_session->name() + _("-template"));
 	prompter.add_button (Gtk::Stock::SAVE, Gtk::RESPONSE_ACCEPT);
 
 	switch (prompter.run()) {
@@ -2113,7 +2112,7 @@ ARDOUR_UI::save_template ()
 		prompter.get_result (name);
 
 		if (name.length()) {
-			session->save_template (name);
+			_session->save_template (name);
 		}
 		break;
 
@@ -2126,7 +2125,7 @@ void
 ARDOUR_UI::edit_metadata ()
 {
 	SessionMetadataEditor dialog;
-	dialog.set_session (session);
+	dialog.set_session (_session);
 	editor->ensure_float (dialog);
 	dialog.run ();
 }
@@ -2135,7 +2134,7 @@ void
 ARDOUR_UI::import_metadata ()
 {
 	SessionMetadataImporter dialog;
-	dialog.set_session (session);
+	dialog.set_session (_session);
 	editor->ensure_float (dialog);
 	dialog.run ();
 }
@@ -2339,7 +2338,7 @@ ARDOUR_UI::build_session_from_nsd (const Glib::ustring& session_path, const Glib
 void
 ARDOUR_UI::idle_load (const Glib::ustring& path)
 {
-	if (session) {
+	if (_session) {
 		if (Glib::file_test (path, Glib::FILE_TEST_IS_DIR)) {
 			/* /path/to/foo => /path/to/foo, foo */
 			load_session (path, basename_nosuffix (path));
@@ -2490,7 +2489,7 @@ ARDOUR_UI::get_session_parameters (bool quit_on_cancel, bool should_be_new)
 
 			ret = load_session (session_path, session_name, template_name);
 			if (!ARDOUR_COMMAND_LINE::immediate_save.empty()) {
-				session->save_state (ARDOUR_COMMAND_LINE::immediate_save, false);
+				_session->save_state (ARDOUR_COMMAND_LINE::immediate_save, false);
 				exit (1);
 			}
 		}
@@ -2594,14 +2593,14 @@ ARDOUR_UI::load_session (const Glib::ustring& path, const Glib::ustring& snap_na
 		goto out;
 	}
 
-	connect_to_session (new_session);
+	set_session (new_session);
 
 	session_loaded = true;
 
 	goto_editor_window ();
 
-	if (session) {
-		session->set_clean ();
+	if (_session) {
+		_session->set_clean ();
 	}
 
 	flush_pending ();
@@ -2653,7 +2652,7 @@ ARDOUR_UI::build_session (const Glib::ustring& path, const Glib::ustring& snap_n
 		return -1;
 	}
 
-	connect_to_session (new_session);
+	set_session (new_session);
 
 	session_loaded = true;
 
@@ -2785,7 +2784,7 @@ require some unused files to continue to exist."));
 
 	dimage->set_alignment(ALIGN_LEFT, ALIGN_TOP);
 
-	const string dead_sound_directory = session->session_directory().dead_sound_path().to_string();
+	const string dead_sound_directory = _session->session_directory().dead_sound_path().to_string();
 
 
 
@@ -2853,7 +2852,7 @@ require some unused files to continue to exist."));
 void
 ARDOUR_UI::cleanup ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		/* shouldn't happen: menu item is insensitive */
 		return;
 	}
@@ -2895,7 +2894,7 @@ After cleanup, unused audio files will be moved to a \
 		act->set_sensitive (false);
 	}
 
-	if (session->cleanup_sources (rep)) {
+	if (_session->cleanup_sources (rep)) {
 		editor->finish_cleanup ();
 		return;
 	}
@@ -2926,14 +2925,14 @@ release an additional\n\
 void
 ARDOUR_UI::flush_trash ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		/* shouldn't happen: menu item is insensitive */
 		return;
 	}
 
 	ARDOUR::CleanupReport rep;
 
-	if (session->cleanup_trash_sources (rep)) {
+	if (_session->cleanup_trash_sources (rep)) {
 		return;
 	}
 
@@ -2952,12 +2951,12 @@ ARDOUR_UI::add_route (Gtk::Window* float_window)
 {
 	int count;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
 	if (add_route_dialog == 0) {
-		add_route_dialog = new AddRouteDialog (*session);
+		add_route_dialog = new AddRouteDialog (_session);
 		if (float_window) {
 			add_route_dialog->set_transient_for (*float_window);
 		}
@@ -2987,7 +2986,7 @@ ARDOUR_UI::add_route (Gtk::Window* float_window)
 	string template_path = add_route_dialog->track_template();
 
 	if (!template_path.empty()) {
-		session->new_route_from_template (count, template_path);
+		_session->new_route_from_template (count, template_path);
 		return;
 	}
 
@@ -3001,7 +3000,7 @@ ARDOUR_UI::add_route (Gtk::Window* float_window)
 	AutoConnectOption oac = Config->get_output_auto_connect();
 
 	if (oac & AutoConnectMaster) {
-		output_chan = (session->master_out() ? session->master_out()->n_inputs().n_audio() : input_chan);
+		output_chan = (_session->master_out() ? _session->master_out()->n_inputs().n_audio() : input_chan);
 	} else {
 		output_chan = input_chan;
 	}
@@ -3031,8 +3030,8 @@ ARDOUR_UI::mixer_settings () const
 {
 	XMLNode* node = 0;
 
-	if (session) {
-		node = session->instant_xml(X_("Mixer"));
+	if (_session) {
+		node = _session->instant_xml(X_("Mixer"));
 	} else {
 		node = Config->instant_xml(X_("Mixer"));
 	}
@@ -3049,8 +3048,8 @@ ARDOUR_UI::editor_settings () const
 {
 	XMLNode* node = 0;
 
-	if (session) {
-		node = session->instant_xml(X_("Editor"));
+	if (_session) {
+		node = _session->instant_xml(X_("Editor"));
 	} else {
 		node = Config->instant_xml(X_("Editor"));
 	}
@@ -3098,17 +3097,17 @@ ARDOUR_UI::halt_on_xrun_message ()
 void
 ARDOUR_UI::xrun_handler(nframes_t where)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
 	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::xrun_handler, where)
 
-	if (session && Config->get_create_xrun_marker() && session->actively_recording()) {
+	if (_session && Config->get_create_xrun_marker() && _session->actively_recording()) {
 		create_xrun_marker(where);
 	}
 
-	if (session && Config->get_stop_recording_on_xrun() && session->actively_recording()) {
+	if (_session && Config->get_stop_recording_on_xrun() && _session->actively_recording()) {
 		halt_on_xrun_message ();
 	}
 }
@@ -3353,15 +3352,15 @@ ARDOUR_UI::update_transport_clocks (nframes_t pos)
 void
 ARDOUR_UI::record_state_changed ()
 {
-	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::record_state_changed)
+	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::record_state_changed);
 
-	if (!session || !big_clock_window) {
+	if (!_session || !big_clock_window) {
 		/* why bother - the clock isn't visible */
 		return;
 	}
 
-	Session::RecordState const r = session->record_status ();
-	bool const h = session->have_rec_enabled_diskstream ();
+	Session::RecordState const r = _session->record_status ();
+	bool const h = _session->have_rec_enabled_diskstream ();
 
 	if (r == Session::Recording && h)  {
 		big_clock.set_widget_name ("BigClockRecording");
@@ -3373,8 +3372,8 @@ ARDOUR_UI::record_state_changed ()
 bool
 ARDOUR_UI::first_idle ()
 {
-	if (session) {
-		session->allow_auto_play (true);
+	if (_session) {
+		_session->allow_auto_play (true);
 	}
 
 	if (editor) {
@@ -3394,8 +3393,8 @@ ARDOUR_UI::store_clock_modes ()
 		node->add_property ((*x)->name().c_str(), enum_2_string ((*x)->mode()));
 	}
 
-	session->add_extra_xml (*node);
-	session->set_dirty ();
+	_session->add_extra_xml (*node);
+	_session->set_dirty ();
 }
 
 
diff --git a/gtk2_ardour/ardour_ui.h b/gtk2_ardour/ardour_ui.h
index f356db6c0a..d14aa7ce0c 100644
--- a/gtk2_ardour/ardour_ui.h
+++ b/gtk2_ardour/ardour_ui.h
@@ -61,6 +61,7 @@
 #include "ardour/ardour.h"
 #include "ardour/types.h"
 #include "ardour/utils.h"
+#include "ardour/session_handle.h"
 
 #include "audio_clock.h"
 #include "ardour_dialog.h"
@@ -100,7 +101,7 @@ namespace ARDOUR {
 extern sigc::signal<void>  ColorsChanged;
 extern sigc::signal<void>  DPIReset;
 
-class ARDOUR_UI : public Gtkmm2ext::UI
+class ARDOUR_UI : public Gtkmm2ext::UI, public ARDOUR::SessionHandlePtr
 {
   public:
 	ARDOUR_UI (int *argcp, char **argvp[]);
@@ -132,7 +133,7 @@ class ARDOUR_UI : public Gtkmm2ext::UI
 			   nframes_t initial_length);
 	bool session_is_new() const { return _session_is_new; }
 
-	ARDOUR::Session* the_session() { return session; }
+	ARDOUR::Session* the_session() { return _session; }
 
 	bool will_create_new_session_automatically() const {
 		return _will_create_new_session_automatically;
@@ -255,7 +256,6 @@ class ARDOUR_UI : public Gtkmm2ext::UI
   private:
 	ArdourStartup*      _startup;
 	ARDOUR::AudioEngine *engine;
-	ARDOUR::Session      *session;
 	Gtk::Tooltips        _tooltips;
 
 	void                goto_editor_window ();
@@ -551,7 +551,7 @@ class ARDOUR_UI : public Gtkmm2ext::UI
 	void toggle_roll (bool with_abort, bool roll_out_of_bounded_mode);
 
 	bool _session_is_new;
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 	void connect_dependents_to_session (ARDOUR::Session *);
 	void we_have_dependents ();
 
diff --git a/gtk2_ardour/ardour_ui2.cc b/gtk2_ardour/ardour_ui2.cc
index 97fb9c742a..ab772389a7 100644
--- a/gtk2_ardour/ardour_ui2.cc
+++ b/gtk2_ardour/ardour_ui2.cc
@@ -468,27 +468,27 @@ ARDOUR_UI::auditioning_changed (bool onoff)
 void
 ARDOUR_UI::audition_alert_toggle ()
 {
-	if (session) {
-		session->cancel_audition();
+	if (_session) {
+		_session->cancel_audition();
 	}
 }
 
 void
 ARDOUR_UI::solo_alert_toggle ()
 {
-	if (session) {
-		session->set_solo (session->get_routes(), !session->soloing());
+	if (_session) {
+		_session->set_solo (_session->get_routes(), !_session->soloing());
 	}
 }
 
 void
 ARDOUR_UI::solo_blink (bool onoff)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	if (session->soloing()) {
+	if (_session->soloing()) {
 		if (onoff) {
 			solo_alert_button.set_state (STATE_ACTIVE);
 		} else {
@@ -503,13 +503,13 @@ ARDOUR_UI::solo_blink (bool onoff)
 void
 ARDOUR_UI::sync_blink (bool onoff)
 {
-	if (session == 0 || !session->config.get_external_sync()) {
+	if (_session == 0 || !_session->config.get_external_sync()) {
 		/* internal sync */
 		sync_button.set_visual_state (0);
 		return;
 	}
 
-	if (!session->transport_locked()) {
+	if (!_session->transport_locked()) {
 		/* not locked, so blink on and off according to the onoff argument */
 
 		if (onoff) {
@@ -526,11 +526,11 @@ ARDOUR_UI::sync_blink (bool onoff)
 void
 ARDOUR_UI::audition_blink (bool onoff)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	if (session->is_auditioning()) {
+	if (_session->is_auditioning()) {
 		if (onoff) {
 			auditioning_alert_button.set_state (STATE_ACTIVE);
 		} else {
@@ -602,7 +602,7 @@ ARDOUR_UI::set_shuttle_max_speed (float speed)
 gint
 ARDOUR_UI::shuttle_box_button_press (GdkEventButton* ev)
 {
-	if (!session) {
+	if (!_session) {
 		return true;
 	}
 
@@ -634,7 +634,7 @@ ARDOUR_UI::shuttle_box_button_press (GdkEventButton* ev)
 gint
 ARDOUR_UI::shuttle_box_button_release (GdkEventButton* ev)
 {
-	if (!session) {
+	if (!_session) {
 		return true;
 	}
 
@@ -644,23 +644,23 @@ ARDOUR_UI::shuttle_box_button_release (GdkEventButton* ev)
 		shuttle_grabbed = false;
 		shuttle_box.remove_modal_grab ();
 		if (Config->get_shuttle_behaviour() == Sprung) {
-			if (session->config.get_auto_play() || roll_button.get_visual_state()) {
+			if (_session->config.get_auto_play() || roll_button.get_visual_state()) {
 				shuttle_fract = SHUTTLE_FRACT_SPEED1;
-				session->request_transport_speed (1.0);
+				_session->request_transport_speed (1.0);
 				stop_button.set_visual_state (0);
 				roll_button.set_visual_state (1);
 			} else {
 				shuttle_fract = 0;
-				session->request_transport_speed (0.0);
+				_session->request_transport_speed (0.0);
 			}
 			shuttle_box.queue_draw ();
 		}
 		return true;
 
 	case 2:
-		if (session->transport_rolling()) {
+		if (_session->transport_rolling()) {
 			shuttle_fract = SHUTTLE_FRACT_SPEED1;
-			session->request_transport_speed (1.0);
+			_session->request_transport_speed (1.0);
 			stop_button.set_visual_state (0);
 			roll_button.set_visual_state (1);
 		} else {
@@ -683,7 +683,7 @@ ARDOUR_UI::shuttle_box_button_release (GdkEventButton* ev)
 gint
 ARDOUR_UI::shuttle_box_scroll (GdkEventScroll* ev)
 {
-	if (!session) {
+	if (!_session) {
 		return true;
 	}
 
@@ -708,7 +708,7 @@ ARDOUR_UI::shuttle_box_scroll (GdkEventScroll* ev)
 gint
 ARDOUR_UI::shuttle_box_motion (GdkEventMotion* ev)
 {
-	if (!session || !shuttle_grabbed) {
+	if (!_session || !shuttle_grabbed) {
 		return true;
 	}
 
@@ -763,7 +763,7 @@ ARDOUR_UI::use_shuttle_fract (bool force)
 		semitones = round (shuttle_fract / step);
 		speed = pow (2.0, (semitones / 12.0));
 
-		session->request_transport_speed (speed);
+		_session->request_transport_speed (speed);
 
 	} else {
 
@@ -778,7 +778,7 @@ ARDOUR_UI::use_shuttle_fract (bool force)
 			fract = -fract;
 		}
 
-		session->request_transport_speed (shuttle_max_speed * fract);
+		_session->request_transport_speed (shuttle_max_speed * fract);
 	}
 
 	shuttle_box.queue_draw ();
@@ -834,7 +834,7 @@ ARDOUR_UI::shuttle_style_changed ()
 void
 ARDOUR_UI::update_speed_display ()
 {
-	if (!session) {
+	if (!_session) {
 		if (last_speed_displayed != 0) {
 			speed_display_label.set_text (_("stop"));
 			last_speed_displayed = 0;
@@ -843,7 +843,7 @@ ARDOUR_UI::update_speed_display ()
 	}
 
 	char buf[32];
-	float x = session->transport_speed ();
+	float x = _session->transport_speed ();
 
 	if (x != last_speed_displayed) {
 
diff --git a/gtk2_ardour/ardour_ui_dependents.cc b/gtk2_ardour/ardour_ui_dependents.cc
index d02fd41def..e1d0054891 100644
--- a/gtk2_ardour/ardour_ui_dependents.cc
+++ b/gtk2_ardour/ardour_ui_dependents.cc
@@ -65,9 +65,9 @@ void
 ARDOUR_UI::connect_dependents_to_session (ARDOUR::Session *s)
 {
 	BootMessage (_("Setup Editor"));
-	editor->connect_to_session (s);
+	editor->set_session (s);
 	BootMessage (_("Setup Mixer"));
-	mixer->connect_to_session (s);
+	mixer->set_session (s);
 
 	/* its safe to do this now */
 
diff --git a/gtk2_ardour/ardour_ui_dialogs.cc b/gtk2_ardour/ardour_ui_dialogs.cc
index 9b9bc3c1e2..9db664199c 100644
--- a/gtk2_ardour/ardour_ui_dialogs.cc
+++ b/gtk2_ardour/ardour_ui_dialogs.cc
@@ -47,25 +47,40 @@ using namespace Gtk;
 using namespace Gtkmm2ext;
 
 void
-ARDOUR_UI::connect_to_session (Session *s)
+ARDOUR_UI::set_session (Session *s)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
 
-	session->Xrun.connect (sigc::mem_fun(*this, &ARDOUR_UI::xrun_handler));
-	session->RecordStateChanged.connect (sigc::mem_fun (*this, &ARDOUR_UI::record_state_changed));
+	if (location_ui) {
+		location_ui->set_session(s);
+	}
+
+	if (route_params) {
+		route_params->set_session (s);
+	}
+
+	primary_clock.set_session (s);
+	secondary_clock.set_session (s);
+	big_clock.set_session (s);
+	preroll_clock.set_session (s);
+	postroll_clock.set_session (s);
+	
+	if (!_session) {
+		return;
+	}
 
 	/* sensitize menu bar options that are now valid */
 
 	ActionManager::set_sensitive (ActionManager::session_sensitive_actions, true);
-	ActionManager::set_sensitive (ActionManager::write_sensitive_actions, session->writable());
+	ActionManager::set_sensitive (ActionManager::write_sensitive_actions, _session->writable());
 
-	if (session->locations()->num_range_markers()) {
+	if (_session->locations()->num_range_markers()) {
 		ActionManager::set_sensitive (ActionManager::range_sensitive_actions, true);
 	} else {
 		ActionManager::set_sensitive (ActionManager::range_sensitive_actions, false);
 	}
 
-	if (!session->control_out()) {
+	if (!_session->control_out()) {
 		Glib::RefPtr<Action> act = ActionManager::get_action (X_("options"), X_("SoloViaBus"));
 		if (act) {
 			act->set_sensitive (false);
@@ -87,19 +102,9 @@ ARDOUR_UI::connect_to_session (Session *s)
 	ActionManager::set_sensitive (ActionManager::point_selection_sensitive_actions, false);
 	ActionManager::set_sensitive (ActionManager::playlist_selection_sensitive_actions, false);
 
-	session->locations()->added.connect (sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change));
-	session->locations()->removed.connect (sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change));
-
 	rec_button.set_sensitive (true);
 	shuttle_box.set_sensitive (true);
-
-	if (location_ui) {
-		location_ui->set_session(s);
-	}
-
-	if (route_params) {
-		route_params->set_session (s);
-	}
+	solo_alert_button.set_active (_session->soloing());
 
 	setup_session_options ();
 
@@ -108,30 +113,15 @@ ARDOUR_UI::connect_to_session (Session *s)
 	Blink.connect (sigc::mem_fun(*this, &ARDOUR_UI::sync_blink));
 	Blink.connect (sigc::mem_fun(*this, &ARDOUR_UI::audition_blink));
 
-	/* these are all need to be handled in an RT-safe and MT way, so don't
-	   do any GUI work, just queue it for handling by the GUI thread.
-	*/
-
-	session->TransportStateChange.connect (sigc::mem_fun(*this, &ARDOUR_UI::map_transport_state));
-
-	/* alert the user to these things happening */
-
-	session->AuditionActive.connect (sigc::mem_fun(*this, &ARDOUR_UI::auditioning_changed));
-	session->SoloActive.connect (sigc::mem_fun(*this, &ARDOUR_UI::soloing_changed));
-
-	solo_alert_button.set_active (session->soloing());
+	_session_connections.add_connection (_session->Xrun.connect (sigc::mem_fun(*this, &ARDOUR_UI::xrun_handler)));
+	_session_connections.add_connection (_session->RecordStateChanged.connect (sigc::mem_fun (*this, &ARDOUR_UI::record_state_changed)));
+	_session_connections.add_connection (_session->locations()->added.connect (sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change)));
+	_session_connections.add_connection (_session->locations()->removed.connect (sigc::mem_fun (*this, &ARDOUR_UI::handle_locations_change)));
+	_session_connections.add_connection (_session->TransportStateChange.connect (sigc::mem_fun(*this, &ARDOUR_UI::map_transport_state)));
+	_session_connections.add_connection (_session->AuditionActive.connect (sigc::mem_fun(*this, &ARDOUR_UI::auditioning_changed)));
+	_session_connections.add_connection (_session->SoloActive.connect (sigc::mem_fun(*this, &ARDOUR_UI::soloing_changed)));
+	_session_connections.add_connection (_session->DirtyChanged.connect (sigc::mem_fun(*this, &ARDOUR_UI::update_autosave)));
 
-	/* update autochange callback on dirty state changing */
-
-	session->DirtyChanged.connect (sigc::mem_fun(*this, &ARDOUR_UI::update_autosave));
-
-	/* can't be auditioning here */
-
-	primary_clock.set_session (s);
-	secondary_clock.set_session (s);
-	big_clock.set_session (s);
-	preroll_clock.set_session (s);
-	postroll_clock.set_session (s);
 
 	/* Clocks are on by default after we are connected to a session, so show that here.
 	*/
@@ -160,14 +150,14 @@ ARDOUR_UI::connect_to_session (Session *s)
 int
 ARDOUR_UI::unload_session (bool hide_stuff)
 {
-	if (session && session->dirty()) {
+	if (_session && _session->dirty()) {
 		switch (ask_about_saving_session (_("close"))) {
 		case -1:
 			// cancel
 			return 1;
 
 		case 1:
-			session->save_state ("");
+			_session->save_state ("");
 			break;
 		}
 	}
@@ -195,14 +185,7 @@ ARDOUR_UI::unload_session (bool hide_stuff)
 
 	Blink.clear ();
 
-	primary_clock.set_session (0);
-	secondary_clock.set_session (0);
-	big_clock.set_session (0);
-	preroll_clock.set_session (0);
-	postroll_clock.set_session (0);
-
-	delete session;
-	session = 0;
+	delete _session;
 
 	update_buffer_load ();
 
@@ -231,7 +214,7 @@ ARDOUR_UI::toggle_rc_options_window ()
 	if (rc_option_editor == 0) {
 		rc_option_editor = new RCOptionEditor;
 		rc_option_editor->signal_unmap().connect(sigc::bind (sigc::ptr_fun(&ActionManager::uncheck_toggleaction), X_("<Actions>/Common/ToggleRCOptionsEditor")));
-		rc_option_editor->set_session (session);
+		rc_option_editor->set_session (_session);
 	}
 
 	RefPtr<Action> act = ActionManager::get_action (X_("Common"), X_("ToggleRCOptionsEditor"));
@@ -251,7 +234,7 @@ void
 ARDOUR_UI::toggle_session_options_window ()
 {
 	if (session_option_editor == 0) {
-		session_option_editor = new SessionOptionEditor (session);
+		session_option_editor = new SessionOptionEditor (_session);
 		session_option_editor->signal_unmap().connect(sigc::bind (sigc::ptr_fun(&ActionManager::uncheck_toggleaction), X_("<Actions>/Common/ToggleSessionOptionsEditor")));
 	}
 
@@ -273,7 +256,7 @@ ARDOUR_UI::create_location_ui ()
 {
 	if (location_ui == 0) {
 		location_ui = new LocationUIWindow ();
-		location_ui->set_session (session);
+		location_ui->set_session (_session);
 		location_ui->signal_unmap().connect (sigc::bind (sigc::ptr_fun(&ActionManager::uncheck_toggleaction), X_("<Actions>/Common/ToggleLocations")));
 	}
 	return 0;
@@ -340,7 +323,7 @@ void
 ARDOUR_UI::create_bundle_manager ()
 {
 	if (bundle_manager == 0) {
-		bundle_manager = new BundleManager (session);
+		bundle_manager = new BundleManager (_session);
 		bundle_manager->signal_unmap().connect (sigc::bind (sigc::ptr_fun (&ActionManager::uncheck_toggleaction), X_("<Actions>/Common/ToggleBundleManager")));
 	}
 }
@@ -368,7 +351,7 @@ ARDOUR_UI::create_route_params ()
 {
 	if (route_params == 0) {
 		route_params = new RouteParams_UI ();
-		route_params->set_session (session);
+		route_params->set_session (_session);
 		route_params->signal_unmap().connect (sigc::bind(sigc::ptr_fun(&ActionManager::uncheck_toggleaction), X_("<Actions>/Common/ToggleInspector")));
 	}
 	return 0;
@@ -397,8 +380,8 @@ ARDOUR_UI::toggle_route_params_window ()
 void
 ARDOUR_UI::handle_locations_change (Location *)
 {
-	if (session) {
-		if (session->locations()->num_range_markers()) {
+	if (_session) {
+		if (_session->locations()->num_range_markers()) {
 			ActionManager::set_sensitive (ActionManager::range_sensitive_actions, true);
 		} else {
 			ActionManager::set_sensitive (ActionManager::range_sensitive_actions, false);
diff --git a/gtk2_ardour/ardour_ui_options.cc b/gtk2_ardour/ardour_ui_options.cc
index 592750a81b..20d492c71b 100644
--- a/gtk2_ardour/ardour_ui_options.cc
+++ b/gtk2_ardour/ardour_ui_options.cc
@@ -49,13 +49,13 @@ using namespace PBD;
 void
 ARDOUR_UI::toggle_external_sync()
 {
-	ActionManager::toggle_config_state_foo ("Transport", "ToggleExternalSync", sigc::mem_fun (session->config, &SessionConfiguration::set_external_sync), sigc::mem_fun (session->config, &SessionConfiguration::get_external_sync));
+	ActionManager::toggle_config_state_foo ("Transport", "ToggleExternalSync", sigc::mem_fun (_session->config, &SessionConfiguration::set_external_sync), sigc::mem_fun (_session->config, &SessionConfiguration::get_external_sync));
 }
 
 void
 ARDOUR_UI::toggle_time_master ()
 {
-	ActionManager::toggle_config_state_foo ("Transport", "ToggleTimeMaster", sigc::mem_fun (session->config, &SessionConfiguration::set_jack_time_master), sigc::mem_fun (session->config, &SessionConfiguration::get_jack_time_master));
+	ActionManager::toggle_config_state_foo ("Transport", "ToggleTimeMaster", sigc::mem_fun (_session->config, &SessionConfiguration::set_jack_time_master), sigc::mem_fun (_session->config, &SessionConfiguration::get_jack_time_master));
 }
 
 void
@@ -91,19 +91,19 @@ ARDOUR_UI::toggle_send_midi_feedback ()
 void
 ARDOUR_UI::toggle_auto_input ()
 {
-	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoInput", sigc::mem_fun (session->config, &SessionConfiguration::set_auto_input), sigc::mem_fun (session->config, &SessionConfiguration::get_auto_input));
+	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoInput", sigc::mem_fun (_session->config, &SessionConfiguration::set_auto_input), sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_input));
 }
 
 void
 ARDOUR_UI::toggle_auto_play ()
 {
-	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoPlay", sigc::mem_fun (session->config, &SessionConfiguration::set_auto_play), sigc::mem_fun (session->config, &SessionConfiguration::get_auto_play));
+	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoPlay", sigc::mem_fun (_session->config, &SessionConfiguration::set_auto_play), sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_play));
 }
 
 void
 ARDOUR_UI::toggle_auto_return ()
 {
-	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoReturn", sigc::mem_fun (session->config, &SessionConfiguration::set_auto_return), sigc::mem_fun (session->config, &SessionConfiguration::get_auto_return));
+	ActionManager::toggle_config_state_foo ("Transport", "ToggleAutoReturn", sigc::mem_fun (_session->config, &SessionConfiguration::set_auto_return), sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_return));
 }
 
 void
@@ -171,8 +171,8 @@ ARDOUR_UI::toggle_punch_in ()
 		return;
 	}
 
-	if (tact->get_active() != session->config.get_punch_in()) {
-		session->config.set_punch_in (tact->get_active ());
+	if (tact->get_active() != _session->config.get_punch_in()) {
+		_session->config.set_punch_in (tact->get_active ());
 	}
 
 	if (tact->get_active()) {
@@ -197,8 +197,8 @@ ARDOUR_UI::toggle_punch_out ()
 		return;
 	}
 
-	if (tact->get_active() != session->config.get_punch_out()) {
-		session->config.set_punch_out (tact->get_active ());
+	if (tact->get_active() != _session->config.get_punch_out()) {
+		_session->config.set_punch_out (tact->get_active ());
 	}
 
 	if (tact->get_active()) {
@@ -234,7 +234,7 @@ ARDOUR_UI::show_loop_punch_ruler_and_disallow_hide ()
 void
 ARDOUR_UI::reenable_hide_loop_punch_ruler_if_appropriate ()
 {
-	if (!session->config.get_punch_in() && !session->config.get_punch_out()) {
+	if (!_session->config.get_punch_in() && !_session->config.get_punch_out()) {
 		/* if punch in/out are now both off, reallow hiding of the loop/punch ruler */
 		Glib::RefPtr<Action> act = ActionManager::get_action (X_("Rulers"), "toggle-loop-punch-ruler");
 		if (act) {
@@ -249,7 +249,7 @@ ARDOUR_UI::toggle_video_sync()
 	Glib::RefPtr<Action> act = ActionManager::get_action ("Transport", "ToggleVideoSync");
 	if (act) {
 		Glib::RefPtr<ToggleAction> tact = Glib::RefPtr<ToggleAction>::cast_dynamic(act);
-		session->config.set_use_video_sync (tact->get_active());
+		_session->config.set_use_video_sync (tact->get_active());
 	}
 }
 
@@ -270,19 +270,19 @@ ARDOUR_UI::toggle_editing_space()
 void
 ARDOUR_UI::setup_session_options ()
 {
-	session->config.ParameterChanged.connect (sigc::mem_fun (*this, &ARDOUR_UI::parameter_changed));
+	_session->config.ParameterChanged.connect (sigc::mem_fun (*this, &ARDOUR_UI::parameter_changed));
 	boost::function<void (std::string)> pc (boost::bind (&ARDOUR_UI::parameter_changed, this, _1));
-	session->config.map_parameters (pc);
+	_session->config.map_parameters (pc);
 }
 
 #if 0
 void
 ARDOUR_UI::handle_sync_change ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
-	if (!session->config.get_external_sync()) {
+	if (!_session->config.get_external_sync()) {
 		sync_button.set_label (_("Internal"));
 		ActionManager::get_action ("Transport", "ToggleAutoPlay")->set_sensitive (true);
 		ActionManager::get_action ("Transport", "ToggleAutoReturn")->set_sensitive (true);
@@ -303,14 +303,14 @@ ARDOUR_UI::parameter_changed (std::string p)
 
 	if (p == "external-sync") {
 
-		ActionManager::map_some_state ("Transport", "ToggleExternalSync", sigc::mem_fun (session->config, &SessionConfiguration::get_external_sync));
+		ActionManager::map_some_state ("Transport", "ToggleExternalSync", sigc::mem_fun (_session->config, &SessionConfiguration::get_external_sync));
 
-		if (!session->config.get_external_sync()) {
+		if (!_session->config.get_external_sync()) {
 			sync_button.set_label (_("Internal"));
 			ActionManager::get_action ("Transport", "ToggleAutoPlay")->set_sensitive (true);
 			ActionManager::get_action ("Transport", "ToggleAutoReturn")->set_sensitive (true);
 		} else {
-			sync_button.set_label (sync_source_to_string (session->config.get_sync_source()));
+			sync_button.set_label (sync_source_to_string (_session->config.get_sync_source()));
 			/* XXX need to make auto-play is off as well as insensitive */
 			ActionManager::get_action ("Transport", "ToggleAutoPlay")->set_sensitive (false);
 			ActionManager::get_action ("Transport", "ToggleAutoReturn")->set_sensitive (false);
@@ -339,27 +339,27 @@ ARDOUR_UI::parameter_changed (std::string p)
 	} else if (p == "midi-feedback") {
 		ActionManager::map_some_state ("options", "SendMIDIfeedback", &RCConfiguration::get_midi_feedback);
 	} else if (p == "auto-play") {
-		ActionManager::map_some_state ("Transport", "ToggleAutoPlay", sigc::mem_fun (session->config, &SessionConfiguration::get_auto_play));
+		ActionManager::map_some_state ("Transport", "ToggleAutoPlay", sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_play));
 	} else if (p == "auto-return") {
-		ActionManager::map_some_state ("Transport", "ToggleAutoReturn", sigc::mem_fun (session->config, &SessionConfiguration::get_auto_return));
+		ActionManager::map_some_state ("Transport", "ToggleAutoReturn", sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_return));
 	} else if (p == "auto-input") {
-		ActionManager::map_some_state ("Transport", "ToggleAutoInput", sigc::mem_fun (session->config, &SessionConfiguration::get_auto_input));
+		ActionManager::map_some_state ("Transport", "ToggleAutoInput", sigc::mem_fun (_session->config, &SessionConfiguration::get_auto_input));
 	} else if (p == "punch-out") {
-		ActionManager::map_some_state ("Transport", "TogglePunchOut", sigc::mem_fun (session->config, &SessionConfiguration::get_punch_out));
-		if (!session->config.get_punch_out()) {
+		ActionManager::map_some_state ("Transport", "TogglePunchOut", sigc::mem_fun (_session->config, &SessionConfiguration::get_punch_out));
+		if (!_session->config.get_punch_out()) {
 			unset_dual_punch ();
 		}
 	} else if (p == "punch-in") {
-		ActionManager::map_some_state ("Transport", "TogglePunchIn", sigc::mem_fun (session->config, &SessionConfiguration::get_punch_in));
-		if (!session->config.get_punch_in()) {
+		ActionManager::map_some_state ("Transport", "TogglePunchIn", sigc::mem_fun (_session->config, &SessionConfiguration::get_punch_in));
+		if (!_session->config.get_punch_in()) {
 			unset_dual_punch ();
 		}
 	} else if (p == "clicking") {
 		ActionManager::map_some_state ("Transport", "ToggleClick", &RCConfiguration::get_clicking);
 	} else if (p == "jack-time-master") {
-		ActionManager::map_some_state ("Transport",  "ToggleTimeMaster", sigc::mem_fun (session->config, &SessionConfiguration::get_jack_time_master));
+		ActionManager::map_some_state ("Transport",  "ToggleTimeMaster", sigc::mem_fun (_session->config, &SessionConfiguration::get_jack_time_master));
 	} else if (p == "use-video-sync") {
-		ActionManager::map_some_state ("Transport",  "ToggleVideoSync", sigc::mem_fun (session->config, &SessionConfiguration::get_use_video_sync));
+		ActionManager::map_some_state ("Transport",  "ToggleVideoSync", sigc::mem_fun (_session->config, &SessionConfiguration::get_use_video_sync));
 	} else if (p == "shuttle-behaviour") {
 
 		switch (Config->get_shuttle_behaviour ()) {
@@ -367,10 +367,10 @@ ARDOUR_UI::parameter_changed (std::string p)
 			shuttle_style_button.set_active_text (_("sprung"));
 			shuttle_fract = 0.0;
 			shuttle_box.queue_draw ();
-			if (session) {
-				if (session->transport_rolling()) {
+			if (_session) {
+				if (_session->transport_rolling()) {
 					shuttle_fract = SHUTTLE_FRACT_SPEED1;
-					session->request_transport_speed (1.0);
+					_session->request_transport_speed (1.0);
 				}
 			}
 			break;
@@ -401,9 +401,9 @@ ARDOUR_UI::reset_main_clocks ()
 {
 	ENSURE_GUI_THREAD (*this, &ARDOUR_UI::reset_main_clocks)
 
-	if (session) {
-		primary_clock.set (session->audible_frame(), true);
-		secondary_clock.set (session->audible_frame(), true);
+	if (_session) {
+		primary_clock.set (_session->audible_frame(), true);
+		secondary_clock.set (_session->audible_frame(), true);
 	} else {
 		primary_clock.set (0, true);
 		secondary_clock.set (0, true);
diff --git a/gtk2_ardour/audio_clock.cc b/gtk2_ardour/audio_clock.cc
index 68df057b95..c37c6cab9c 100644
--- a/gtk2_ardour/audio_clock.cc
+++ b/gtk2_ardour/audio_clock.cc
@@ -64,9 +64,8 @@ const uint32_t AudioClock::field_length[(int) AudioClock::AudioFrames+1] = {
 	10   /* Audio Frame */
 };
 
-AudioClock::AudioClock (
-	std::string clock_name, bool transient, std::string widget_name, bool allow_edit, bool follows_playhead, bool duration, bool with_info
-	)
+AudioClock::AudioClock (std::string clock_name, bool transient, std::string widget_name, 
+			bool allow_edit, bool follows_playhead, bool duration, bool with_info)
 	: _name (clock_name),
 	  is_transient (transient),
 	  is_duration (duration),
@@ -81,7 +80,6 @@ AudioClock::AudioClock (
 	  b2 ("|"),
 	  last_when(0)
 {
-	session = 0;
 	last_when = 0;
 	last_pdelta = 0;
 	last_sdelta = 0;
@@ -419,7 +417,7 @@ void
 AudioClock::set (nframes_t when, bool force, nframes_t offset, char which)
 {
 
- 	if ((!force && !is_visible()) || session == 0) {
+ 	if ((!force && !is_visible()) || _session == 0) {
 		return;
 	}
 
@@ -501,7 +499,7 @@ AudioClock::set_frames (nframes_t when, bool /*force*/)
 	audio_frames_label.set_text (buf);
 
 	if (frames_upper_info_label) {
-		nframes_t rate = session->frame_rate();
+		nframes_t rate = _session->frame_rate();
 
 		if (fmod (rate, 1000.0) == 0.000) {
 			sprintf (buf, "%uK", rate/1000);
@@ -513,7 +511,7 @@ AudioClock::set_frames (nframes_t when, bool /*force*/)
 			frames_upper_info_label->set_text (buf);
 		}
 
-		float vid_pullup = session->config.get_video_pullup();
+		float vid_pullup = _session->config.get_video_pullup();
 
 		if (vid_pullup == 0.0) {
 			if (frames_lower_info_label->get_text () != _("none")) {
@@ -538,11 +536,11 @@ AudioClock::set_minsec (nframes_t when, bool force)
 	float secs;
 
 	left = when;
-	hrs = (int) floor (left / (session->frame_rate() * 60.0f * 60.0f));
-	left -= (nframes_t) floor (hrs * session->frame_rate() * 60.0f * 60.0f);
-	mins = (int) floor (left / (session->frame_rate() * 60.0f));
-	left -= (nframes_t) floor (mins * session->frame_rate() * 60.0f);
-	secs = left / (float) session->frame_rate();
+	hrs = (int) floor (left / (_session->frame_rate() * 60.0f * 60.0f));
+	left -= (nframes_t) floor (hrs * _session->frame_rate() * 60.0f * 60.0f);
+	mins = (int) floor (left / (_session->frame_rate() * 60.0f));
+	left -= (nframes_t) floor (mins * _session->frame_rate() * 60.0f);
+	secs = left / (float) _session->frame_rate();
 
 	if (force || hrs != ms_last_hrs) {
 		sprintf (buf, "%02d", hrs);
@@ -570,9 +568,9 @@ AudioClock::set_timecode (nframes_t when, bool force)
 	Timecode::Time timecode;
 
 	if (is_duration) {
-		session->timecode_duration (when, timecode);
+		_session->timecode_duration (when, timecode);
 	} else {
-		session->timecode_time (when, timecode);
+		_session->timecode_time (when, timecode);
 	}
 
 	if (force || timecode.hours != last_hrs || timecode.negative != last_negative) {
@@ -605,7 +603,7 @@ AudioClock::set_timecode (nframes_t when, bool force)
 	}
 
 	if (timecode_upper_info_label) {
-		double timecode_frames = session->timecode_frames_per_second();
+		double timecode_frames = _session->timecode_frames_per_second();
 
 		if ( fmod(timecode_frames, 1.0) == 0.0) {
 			sprintf (buf, "%u", int (timecode_frames));
@@ -618,7 +616,7 @@ AudioClock::set_timecode (nframes_t when, bool force)
 		}
 
 		if ((fabs(timecode_frames - 29.97) < 0.0001) || timecode_frames == 30) {
-			if (session->timecode_drop_frames()) {
+			if (_session->timecode_drop_frames()) {
 				sprintf (buf, "DF");
 			} else {
 				sprintf (buf, "NDF");
@@ -647,12 +645,12 @@ AudioClock::set_bbt (nframes_t when, bool force)
 			bbt.beats = 0;
 			bbt.ticks = 0;
 		} else {
-			session->tempo_map().bbt_time (when, bbt);
+			_session->tempo_map().bbt_time (when, bbt);
 			bbt.bars--;
 			bbt.beats--;
 		}
 	} else {
-		session->tempo_map().bbt_time (when, bbt);
+		_session->tempo_map().bbt_time (when, bbt);
 	}
 
 	sprintf (buf, "%03" PRIu32, bbt.bars);
@@ -677,7 +675,7 @@ AudioClock::set_bbt (nframes_t when, bool force)
 			pos = bbt_reference_time;
 		}
 
-		TempoMetric m (session->tempo_map().metric_at (pos));
+		TempoMetric m (_session->tempo_map().metric_at (pos));
 
 		sprintf (buf, "%-5.2f", m.tempo().beats_per_minute());
 		if (bbt_lower_info_label->get_text() != buf) {
@@ -693,12 +691,12 @@ AudioClock::set_bbt (nframes_t when, bool force)
 void
 AudioClock::set_session (Session *s)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
 
-	if (s) {
+	if (_session) {
 
 		XMLProperty* prop;
-		XMLNode* node = session->extra_xml (X_("ClockModes"));
+		XMLNode* node = _session->extra_xml (X_("ClockModes"));
 		AudioClock::Mode amode;
 
 		if (node) {
@@ -1190,7 +1188,7 @@ AudioClock::field_button_release_event (GdkEventButton *ev, Field field)
 bool
 AudioClock::field_button_press_event (GdkEventButton *ev, Field /*field*/)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return false;
 	}
 
@@ -1236,7 +1234,7 @@ AudioClock::field_button_press_event (GdkEventButton *ev, Field /*field*/)
 bool
 AudioClock::field_button_scroll_event (GdkEventScroll *ev, Field field)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return false;
 	}
 
@@ -1283,7 +1281,7 @@ AudioClock::field_button_scroll_event (GdkEventScroll *ev, Field field)
 bool
 AudioClock::field_motion_notify_event (GdkEventMotion *ev, Field field)
 {
-	if (session == 0 || !dragging) {
+	if (_session == 0 || !dragging) {
 		return false;
 	}
 
@@ -1342,16 +1340,16 @@ AudioClock::get_frames (Field field,nframes_t pos,int dir)
 	BBT_Time bbt;
 	switch (field) {
 	case Timecode_Hours:
-		frames = (nframes_t) floor (3600.0 * session->frame_rate());
+		frames = (nframes_t) floor (3600.0 * _session->frame_rate());
 		break;
 	case Timecode_Minutes:
-		frames = (nframes_t) floor (60.0 * session->frame_rate());
+		frames = (nframes_t) floor (60.0 * _session->frame_rate());
 		break;
 	case Timecode_Seconds:
-		frames = session->frame_rate();
+		frames = _session->frame_rate();
 		break;
 	case Timecode_Frames:
-		frames = (nframes_t) floor (session->frame_rate() / session->timecode_frames_per_second());
+		frames = (nframes_t) floor (_session->frame_rate() / _session->timecode_frames_per_second());
 		break;
 
 	case AudioFrames:
@@ -1359,32 +1357,32 @@ AudioClock::get_frames (Field field,nframes_t pos,int dir)
 		break;
 
 	case MS_Hours:
-		frames = (nframes_t) floor (3600.0 * session->frame_rate());
+		frames = (nframes_t) floor (3600.0 * _session->frame_rate());
 		break;
 	case MS_Minutes:
-		frames = (nframes_t) floor (60.0 * session->frame_rate());
+		frames = (nframes_t) floor (60.0 * _session->frame_rate());
 		break;
 	case MS_Seconds:
-		frames = session->frame_rate();
+		frames = _session->frame_rate();
 		break;
 
 	case Bars:
 		bbt.bars = 1;
 		bbt.beats = 0;
 		bbt.ticks = 0;
-		frames = session->tempo_map().bbt_duration_at(pos,bbt,dir);
+		frames = _session->tempo_map().bbt_duration_at(pos,bbt,dir);
 		break;
 	case Beats:
 		bbt.bars = 0;
 		bbt.beats = 1;
 		bbt.ticks = 0;
-		frames = session->tempo_map().bbt_duration_at(pos,bbt,dir);
+		frames = _session->tempo_map().bbt_duration_at(pos,bbt,dir);
 		break;
 	case Ticks:
 		bbt.bars = 0;
 		bbt.beats = 0;
 		bbt.ticks = 1;
-		frames = session->tempo_map().bbt_duration_at(pos,bbt,dir);
+		frames = _session->tempo_map().bbt_duration_at(pos,bbt,dir);
 		break;
 	}
 
@@ -1459,7 +1457,7 @@ AudioClock::timecode_sanitize_display()
 		seconds_label.set_text("59");
 	}
 
-	switch ((long)rint(session->timecode_frames_per_second())) {
+	switch ((long)rint(_session->timecode_frames_per_second())) {
 	case 24:
 		if (atoi(frames_label.get_text()) > 23) {
 			frames_label.set_text("23");
@@ -1479,7 +1477,7 @@ AudioClock::timecode_sanitize_display()
 		break;
 	}
 
-	if (session->timecode_drop_frames()) {
+	if (_session->timecode_drop_frames()) {
 		if ((atoi(minutes_label.get_text()) % 10) && (atoi(seconds_label.get_text()) == 0) && (atoi(frames_label.get_text()) < 2)) {
 			frames_label.set_text("02");
 		}
@@ -1489,7 +1487,7 @@ AudioClock::timecode_sanitize_display()
 nframes_t
 AudioClock::timecode_frame_from_display () const
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return 0;
 	}
 
@@ -1500,10 +1498,10 @@ AudioClock::timecode_frame_from_display () const
 	timecode.minutes = atoi (minutes_label.get_text());
 	timecode.seconds = atoi (seconds_label.get_text());
 	timecode.frames = atoi (frames_label.get_text());
-	timecode.rate = session->timecode_frames_per_second();
-	timecode.drop= session->timecode_drop_frames();
+	timecode.rate = _session->timecode_frames_per_second();
+	timecode.drop= _session->timecode_drop_frames();
 
-	session->timecode_to_sample( timecode, sample, false /* use_offset */, false /* use_subframes */ );
+	_session->timecode_to_sample( timecode, sample, false /* use_offset */, false /* use_subframes */ );
 
 
 #if 0
@@ -1522,14 +1520,14 @@ AudioClock::timecode_frame_from_display () const
 	Timecode::Time timecode2;
 	nframes_t sample_increment;
 
-	sample_increment = (long)rint(session->frame_rate() / session->timecode_frames_per_second);
+	sample_increment = (long)rint(_session->frame_rate() / _session->timecode_frames_per_second);
 
 #ifdef Timecode_SAMPLE_TEST_1
 	// Test 1: use_offset = false, use_subframes = false
 	cout << "use_offset = false, use_subframes = false" << endl;
 	for (int i = 0; i < 108003; i++) {
-		session->timecode_to_sample( timecode1, sample1, false /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, false /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, false /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, false /* use_offset */, false /* use_subframes */ );
 
 		if ((i > 0) && ( ((sample1 - oldsample) != sample_increment) && ((sample1 - oldsample) != (sample_increment + 1)) && ((sample1 - oldsample) != (sample_increment - 1)))) {
 			cout << "ERROR: sample increment not right: " << (sample1 - oldsample) << " != " << sample_increment << endl;
@@ -1549,7 +1547,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_increment( timecode1 );
+		_session->timecode_increment( timecode1 );
 	}
 
 	cout << "sample_increment: " << sample_increment << endl;
@@ -1568,13 +1566,13 @@ AudioClock::timecode_frame_from_display () const
 	timecode1.subframes = 0;
 	sample1 = oldsample = 0;
 
-	session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
+	_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
 	cout << "Starting at sample: " << sample1 << " -> ";
 	cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 	for (int i = 0; i < 108003; i++) {
-		session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
 
 //     cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << " -> ";
 //     cout << "sample: " << sample1 << endl;
@@ -1599,7 +1597,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_increment( timecode1 );
+		_session->timecode_increment( timecode1 );
 	}
 
 	cout << "sample_increment: " << sample_increment << endl;
@@ -1611,13 +1609,13 @@ AudioClock::timecode_frame_from_display () const
 	// Test 3: use_offset = true, use_subframes = false, decrement
 	cout << "use_offset = true, use_subframes = false, decrement" << endl;
 
-	session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
+	_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
 	cout << "Starting at sample: " << sample1 << " -> ";
 	cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 	for (int i = 0; i < 108003; i++) {
-		session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
 
 //     cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << " -> ";
 //     cout << "sample: " << sample1 << endl;
@@ -1642,7 +1640,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_decrement( timecode1 );
+		_session->timecode_decrement( timecode1 );
 	}
 
 	cout << "sample_decrement: " << sample_increment << endl;
@@ -1663,14 +1661,14 @@ AudioClock::timecode_frame_from_display () const
 		timecode1.subframes = 0;
 		sample1 = oldsample = (sample_increment * sub) / 80;
 
-		session->sample_to_timecode( sample1, timecode1, true /* use_offset */, true /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, true /* use_subframes */ );
 
 		cout << "starting at sample: " << sample1 << " -> ";
 		cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 		for (int i = 0; i < 108003; i++) {
-			session->timecode_to_sample( timecode1, sample1, true /* use_offset */, true /* use_subframes */ );
-			session->sample_to_timecode( sample1, timecode2, true /* use_offset */, true /* use_subframes */ );
+			_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, true /* use_subframes */ );
+			_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, true /* use_subframes */ );
 
 			if ((i > 0) && ( ((sample1 - oldsample) != sample_increment) && ((sample1 - oldsample) != (sample_increment + 1)) && ((sample1 - oldsample) != (sample_increment - 1)))) {
 				cout << "ERROR: sample increment not right: " << (sample1 - oldsample) << " != " << sample_increment << endl;
@@ -1690,7 +1688,7 @@ AudioClock::timecode_frame_from_display () const
 				break;
 			}
 			oldsample = sample1;
-			session->timecode_increment( timecode1 );
+			_session->timecode_increment( timecode1 );
 		}
 
 		cout << "sample_increment: " << sample_increment << endl;
@@ -1698,8 +1696,8 @@ AudioClock::timecode_frame_from_display () const
 		cout << "timecode: " << (timecode2.negative ? "-" : "") << timecode2.hours << ":" << timecode2.minutes << ":" << timecode2.seconds << ":" << timecode2.frames << "::" << timecode2.subframes << endl;
 
 		for (int i = 0; i < 108003; i++) {
-			session->timecode_to_sample( timecode1, sample1, true /* use_offset */, true /* use_subframes */ );
-			session->sample_to_timecode( sample1, timecode2, true /* use_offset */, true /* use_subframes */ );
+			_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, true /* use_subframes */ );
+			_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, true /* use_subframes */ );
 
 			if ((i > 0) && ( ((oldsample - sample1) != sample_increment) && ((oldsample - sample1) != (sample_increment + 1)) && ((oldsample - sample1) != (sample_increment - 1)))) {
 				cout << "ERROR: sample increment not right: " << (oldsample - sample1) << " != " << sample_increment << endl;
@@ -1719,7 +1717,7 @@ AudioClock::timecode_frame_from_display () const
 				break;
 			}
 			oldsample = sample1;
-			session->timecode_decrement( timecode1 );
+			_session->timecode_decrement( timecode1 );
 		}
 
 		cout << "sample_decrement: " << sample_increment << endl;
@@ -1739,15 +1737,15 @@ AudioClock::timecode_frame_from_display () const
 	timecode1.frames = 0;
 	timecode1.subframes = 0;
 	sample1 = oldsample = 0;
-	sample_increment = session->frame_rate();
+	sample_increment = _session->frame_rate();
 
-	session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
+	_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
 	cout << "Starting at sample: " << sample1 << " -> ";
 	cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 	for (int i = 0; i < 3600; i++) {
-		session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
 
 //     cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << " -> ";
 //     cout << "sample: " << sample1 << endl;
@@ -1769,7 +1767,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_increment_seconds( timecode1 );
+		_session->timecode_increment_seconds( timecode1 );
 	}
 
 	cout << "sample_increment: " << sample_increment << endl;
@@ -1788,15 +1786,15 @@ AudioClock::timecode_frame_from_display () const
 	timecode1.frames = 0;
 	timecode1.subframes = 0;
 	sample1 = oldsample = 0;
-	sample_increment = session->frame_rate() * 60;
+	sample_increment = _session->frame_rate() * 60;
 
-	session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
+	_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
 	cout << "Starting at sample: " << sample1 << " -> ";
 	cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 	for (int i = 0; i < 60; i++) {
-		session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
 
 //     cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << " -> ";
 //     cout << "sample: " << sample1 << endl;
@@ -1818,7 +1816,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_increment_minutes( timecode1 );
+		_session->timecode_increment_minutes( timecode1 );
 	}
 
 	cout << "sample_increment: " << sample_increment << endl;
@@ -1836,15 +1834,15 @@ AudioClock::timecode_frame_from_display () const
 	timecode1.frames = 0;
 	timecode1.subframes = 0;
 	sample1 = oldsample = 0;
-	sample_increment = session->frame_rate() * 60 * 60;
+	sample_increment = _session->frame_rate() * 60 * 60;
 
-	session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
+	_session->sample_to_timecode( sample1, timecode1, true /* use_offset */, false /* use_subframes */ );
 	cout << "Starting at sample: " << sample1 << " -> ";
 	cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << endl;
 
 	for (int i = 0; i < 10; i++) {
-		session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
-		session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
+		_session->timecode_to_sample( timecode1, sample1, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode( sample1, timecode2, true /* use_offset */, false /* use_subframes */ );
 
 //     cout << "timecode: " << (timecode1.negative ? "-" : "") << timecode1.hours << ":" << timecode1.minutes << ":" << timecode1.seconds << ":" << timecode1.frames << "::" << timecode1.subframes << " -> ";
 //     cout << "sample: " << sample1 << endl;
@@ -1866,7 +1864,7 @@ AudioClock::timecode_frame_from_display () const
 			break;
 		}
 		oldsample = sample1;
-		session->timecode_increment_hours( timecode1 );
+		_session->timecode_increment_hours( timecode1 );
 	}
 
 	cout << "sample_increment: " << sample_increment << endl;
@@ -1882,7 +1880,7 @@ AudioClock::timecode_frame_from_display () const
 nframes_t
 AudioClock::minsec_frame_from_display () const
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return 0;
 	}
 
@@ -1890,7 +1888,7 @@ AudioClock::minsec_frame_from_display () const
 	int mins = atoi (ms_minutes_label.get_text());
 	float secs = atof (ms_seconds_label.get_text());
 
-	nframes_t sr = session->frame_rate();
+	nframes_t sr = _session->frame_rate();
 
 	return (nframes_t) floor ((hrs * 60.0f * 60.0f * sr) + (mins * 60.0f * sr) + (secs * sr));
 }
@@ -1898,7 +1896,7 @@ AudioClock::minsec_frame_from_display () const
 nframes_t
 AudioClock::bbt_frame_from_display (nframes_t pos) const
 {
-	if (session == 0) {
+	if (_session == 0) {
 		error << "AudioClock::current_time() called with BBT mode but without session!" << endmsg;
 		return 0;
 	}
@@ -1915,7 +1913,7 @@ AudioClock::bbt_frame_from_display (nframes_t pos) const
                any.bbt.beats++;
        }
 
-	nframes_t ret = session->convert_to_frames_at (pos, any);
+	nframes_t ret = _session->convert_to_frames_at (pos, any);
 
 	return ret;
 }
@@ -1924,7 +1922,7 @@ AudioClock::bbt_frame_from_display (nframes_t pos) const
 nframes_t
 AudioClock::bbt_frame_duration_from_display (nframes_t pos) const
 {
-	if (session == 0) {
+	if (_session == 0) {
 		error << "AudioClock::current_time() called with BBT mode but without session!" << endmsg;
 		return 0;
 	}
@@ -1936,7 +1934,7 @@ AudioClock::bbt_frame_duration_from_display (nframes_t pos) const
 	bbt.beats = atoi (beats_label.get_text());
 	bbt.ticks = atoi (ticks_label.get_text());
 
-	return session->tempo_map().bbt_duration_at(pos,bbt,1);
+	return _session->tempo_map().bbt_duration_at(pos,bbt,1);
 }
 
 nframes_t
@@ -1971,21 +1969,21 @@ AudioClock::build_ops_menu ()
 void
 AudioClock::set_from_playhead ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 	
-	set (session->transport_frame());
+	set (_session->transport_frame());
 }
 
 void
 AudioClock::locate ()
 {
-	if (!session || is_duration) {
+	if (!_session || is_duration) {
 		return;
 	}
 	
-	session->request_locate (current_time(), false);
+	_session->request_locate (current_time(), false);
 }
 
 void
diff --git a/gtk2_ardour/audio_clock.h b/gtk2_ardour/audio_clock.h
index 38bb3f1329..1a15cecd7b 100644
--- a/gtk2_ardour/audio_clock.h
+++ b/gtk2_ardour/audio_clock.h
@@ -26,12 +26,13 @@
 #include <gtkmm/label.h>
 #include <gtkmm/frame.h>
 #include "ardour/ardour.h"
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 	class Session;
 }
 
-class AudioClock : public Gtk::HBox
+class AudioClock : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   public:
 	enum Mode {
@@ -72,7 +73,6 @@ class AudioClock : public Gtk::HBox
 	static bool has_focus() { return _has_focus; }
 
   private:
-	ARDOUR::Session  *session;
 	Mode             _mode;
 	uint32_t          key_entry_state;
 	std::string      _name;
diff --git a/gtk2_ardour/audio_region_editor.cc b/gtk2_ardour/audio_region_editor.cc
index ade0b8edb9..2c26f562ff 100644
--- a/gtk2_ardour/audio_region_editor.cc
+++ b/gtk2_ardour/audio_region_editor.cc
@@ -41,7 +41,7 @@ using namespace PBD;
 using namespace std;
 using namespace Gtkmm2ext;
 
-AudioRegionEditor::AudioRegionEditor (Session& s, boost::shared_ptr<AudioRegion> r, AudioRegionView& rv)
+AudioRegionEditor::AudioRegionEditor (Session* s, boost::shared_ptr<AudioRegion> r, AudioRegionView& rv)
 	: RegionEditor (s),
 	  _region (r),
 	  _region_view (rv),
@@ -58,12 +58,12 @@ AudioRegionEditor::AudioRegionEditor (Session& s, boost::shared_ptr<AudioRegion>
 	  gain_adjustment(accurate_coefficient_to_dB(_region->scale_amplitude()), -40.0, +40.0, 0.1, 1.0, 0)	  
 
 {
-	position_clock.set_session (&_session);
-	end_clock.set_session (&_session);
-	length_clock.set_session (&_session);
-	sync_offset_relative_clock.set_session (&_session);
-	sync_offset_absolute_clock.set_session (&_session);
-	start_clock.set_session (&_session);
+	position_clock.set_session (_session);
+	end_clock.set_session (_session);
+	length_clock.set_session (_session);
+	sync_offset_relative_clock.set_session (_session);
+	sync_offset_absolute_clock.set_session (_session);
+	start_clock.set_session (_session);
 
 	name_entry.set_name ("AudioRegionEditorEntry");
 	name_label.set_name ("AudioRegionEditorLabel");
@@ -228,13 +228,13 @@ AudioRegionEditor::connect_editor_events ()
 	gain_adjustment.signal_value_changed().connect (sigc::mem_fun (*this, &AudioRegionEditor::gain_adjustment_changed));
 
 	audition_button.signal_toggled().connect (sigc::mem_fun(*this, &AudioRegionEditor::audition_button_toggled));
-	_session.AuditionActive.connect (sigc::mem_fun(*this, &AudioRegionEditor::audition_state_changed));
+	_session->AuditionActive.connect (sigc::mem_fun(*this, &AudioRegionEditor::audition_state_changed));
 }
 
 void
 AudioRegionEditor::position_clock_changed ()
 {
-	_session.begin_reversible_command (_("change region start position"));
+	_session->begin_reversible_command (_("change region start position"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -242,16 +242,16 @@ AudioRegionEditor::position_clock_changed ()
 		XMLNode &before = pl->get_state();
 		_region->set_position (position_clock.current_time(), this);
 		XMLNode &after = pl->get_state();
-		_session.add_command(new MementoCommand<Playlist>(*pl, &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*pl, &before, &after));
 	}
 
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
 AudioRegionEditor::end_clock_changed ()
 {
-	_session.begin_reversible_command (_("change region end position"));
+	_session->begin_reversible_command (_("change region end position"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -259,10 +259,10 @@ AudioRegionEditor::end_clock_changed ()
 		XMLNode &before = pl->get_state();
 		_region->trim_end (end_clock.current_time(), this);
 		XMLNode &after = pl->get_state();
-		_session.add_command(new MementoCommand<Playlist>(*pl, &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*pl, &before, &after));
 	}
 
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 
 	end_clock.set (_region->position() + _region->length() - 1, true);
 }
@@ -272,7 +272,7 @@ AudioRegionEditor::length_clock_changed ()
 {
 	nframes_t frames = length_clock.current_time();
 
-	_session.begin_reversible_command (_("change region length"));
+	_session->begin_reversible_command (_("change region length"));
 
 	boost::shared_ptr<Playlist> pl = _region->playlist();
 
@@ -280,10 +280,10 @@ AudioRegionEditor::length_clock_changed ()
 		XMLNode &before = pl->get_state();
 		_region->trim_end (_region->position() + frames - 1, this);
 		XMLNode &after = pl->get_state();
-		_session.add_command(new MementoCommand<Playlist>(*pl, &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*pl, &before, &after));
 	}
 
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 
 	length_clock.set (_region->length());
 }
@@ -310,9 +310,9 @@ void
 AudioRegionEditor::audition_button_toggled ()
 {
 	if (audition_button.get_active()) {
-		_session.audition_region (_region);
+		_session->audition_region (_region);
 	} else {
-		_session.cancel_audition ();
+		_session->cancel_audition ();
 	}
 }
 
@@ -385,27 +385,27 @@ AudioRegionEditor::audition_state_changed (bool yn)
 void
 AudioRegionEditor::sync_offset_absolute_clock_changed ()
 {
-	_session.begin_reversible_command (_("change region sync point"));
+	_session->begin_reversible_command (_("change region sync point"));
 
 	XMLNode& before = _region->get_state ();
 	_region->set_sync_position (sync_offset_absolute_clock.current_time());
 	XMLNode& after = _region->get_state ();
-	_session.add_command (new MementoCommand<AudioRegion> (*_region.get(), &before, &after));
+	_session->add_command (new MementoCommand<AudioRegion> (*_region.get(), &before, &after));
 	
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
 AudioRegionEditor::sync_offset_relative_clock_changed ()
 {
-	_session.begin_reversible_command (_("change region sync point"));
+	_session->begin_reversible_command (_("change region sync point"));
 
 	XMLNode& before = _region->get_state ();
 	_region->set_sync_position (sync_offset_relative_clock.current_time() + _region->position ());
 	XMLNode& after = _region->get_state ();
-	_session.add_command (new MementoCommand<AudioRegion> (*_region.get(), &before, &after));
+	_session->add_command (new MementoCommand<AudioRegion> (*_region.get(), &before, &after));
 	
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 bool
diff --git a/gtk2_ardour/audio_region_editor.h b/gtk2_ardour/audio_region_editor.h
index 3de1522734..f4c99917d8 100644
--- a/gtk2_ardour/audio_region_editor.h
+++ b/gtk2_ardour/audio_region_editor.h
@@ -51,7 +51,7 @@ class AudioRegionView;
 class AudioRegionEditor : public RegionEditor
 {
   public:
-	AudioRegionEditor (ARDOUR::Session&, boost::shared_ptr<ARDOUR::AudioRegion>, AudioRegionView& rv);
+	AudioRegionEditor (ARDOUR::Session*, boost::shared_ptr<ARDOUR::AudioRegion>, AudioRegionView& rv);
 	~AudioRegionEditor ();
 
   private:
diff --git a/gtk2_ardour/audio_region_view.cc b/gtk2_ardour/audio_region_view.cc
index 682287bf59..30c426567f 100644
--- a/gtk2_ardour/audio_region_view.cc
+++ b/gtk2_ardour/audio_region_view.cc
@@ -200,15 +200,14 @@ AudioRegionView::init (Gdk::Color const & basic_color, bool wfd)
 
 	setup_fade_handle_positions ();
 
-	if (!trackview.session().config.get_show_region_fades()) {
+	if (!trackview.session()->config.get_show_region_fades()) {
 		set_fade_visibility (false);
 	}
 
 	const string line_name = _region->name() + ":gain";
 
 	if (!Profile->get_sae()) {
-		gain_line = new AudioRegionGainLine (line_name, trackview.session(), *this, *group,
-				audio_region()->envelope());
+		gain_line = new AudioRegionGainLine (line_name, *this, *group, audio_region()->envelope());
 	}
 
 	if (!(_flags & EnvelopeVisible)) {
@@ -360,7 +359,7 @@ AudioRegionView::region_renamed ()
 {
 	Glib::ustring str = RegionView::make_name ();
 
-	if (audio_region()->speed_mismatch (trackview.session().frame_rate())) {
+	if (audio_region()->speed_mismatch (trackview.session()->frame_rate())) {
 		str = string ("*") + str;
 	}
 
@@ -415,7 +414,7 @@ AudioRegionView::reset_width_dependent_items (double pixel_width)
 				fade_in_handle->hide();
 				fade_out_handle->hide();
 			} else {
-				if (trackview.session().config.get_show_region_fades()) {
+				if (trackview.session()->config.get_show_region_fades()) {
 					fade_in_handle->show();
 					fade_out_handle->show();
 				}
@@ -575,7 +574,7 @@ AudioRegionView::reset_fade_in_shape_width (nframes_t width)
 		return;
 	}
 
-	if (trackview.session().config.get_show_region_fades()) {
+	if (trackview.session()->config.get_show_region_fades()) {
 		fade_in_shape->show();
 	}
 
@@ -666,7 +665,7 @@ AudioRegionView::reset_fade_out_shape_width (nframes_t width)
 		return;
 	}
 
-	if (trackview.session().config.get_show_region_fades()) {
+	if (trackview.session()->config.get_show_region_fades()) {
 		fade_out_shape->show();
 	}
 
@@ -869,7 +868,7 @@ AudioRegionView::create_waves ()
 		// cerr << "\tchannel " << n << endl;
 
 		if (wait_for_data) {
-			if (audio_region()->audio_source(n)->peaks_ready (sigc::bind (sigc::mem_fun(*this, &AudioRegionView::peaks_ready_handler), n), data_ready_connection)) {
+			if (audio_region()->audio_source(n)->peaks_ready (boost::bind (&AudioRegionView::peaks_ready_handler, this, n), data_ready_connection)) {
 				// cerr << "\tData is ready\n";
 				create_one_wave (n, true);
 			} else {
@@ -1018,21 +1017,21 @@ AudioRegionView::add_gain_point_event (ArdourCanvas::Item *item, GdkEvent *ev)
 
 	gain_line->view_to_model_coord (x, y);
 
-	trackview.session().begin_reversible_command (_("add gain control point"));
+	trackview.session()->begin_reversible_command (_("add gain control point"));
 	XMLNode &before = audio_region()->envelope()->get_state();
 
 	if (!audio_region()->envelope_active()) {
 		XMLNode &region_before = audio_region()->get_state();
 		audio_region()->set_envelope_active(true);
 		XMLNode &region_after = audio_region()->get_state();
-		trackview.session().add_command (new MementoCommand<AudioRegion>(*(audio_region().get()), &region_before, &region_after));
+		trackview.session()->add_command (new MementoCommand<AudioRegion>(*(audio_region().get()), &region_before, &region_after));
 	}
 
 	audio_region()->envelope()->add (fx, y);
 
 	XMLNode &after = audio_region()->envelope()->get_state();
-	trackview.session().add_command (new MementoCommand<AutomationList>(*audio_region()->envelope().get(), &before, &after));
-	trackview.session().commit_reversible_command ();
+	trackview.session()->add_command (new MementoCommand<AutomationList>(*audio_region()->envelope().get(), &before, &after));
+	trackview.session()->commit_reversible_command ();
 }
 
 void
@@ -1187,7 +1186,7 @@ AudioRegionView::add_ghost (TimeAxisView& tv)
 	ghost->set_colors();
 	ghosts.push_back (ghost);
 
-	ghost->GoingAway.connect (sigc::mem_fun(*this, &AudioRegionView::remove_ghost));
+	ghost->GoingAway.connect (boost::bind (&RegionView::remove_ghost, this, _1));
 
 	return ghost;
 }
diff --git a/gtk2_ardour/audio_streamview.cc b/gtk2_ardour/audio_streamview.cc
index 289035d9bf..85ea02a197 100644
--- a/gtk2_ardour/audio_streamview.cc
+++ b/gtk2_ardour/audio_streamview.cc
@@ -188,9 +188,9 @@ AudioStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wai
 
 	region_views.push_front (region_view);
 
-	/* catch regionview going away */
-	cerr << this << " connected to region " << r << endl;
-	r->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &AudioStreamView::remove_region_view), boost::weak_ptr<Region> (r)));
+	/* catch region going away */
+
+	scoped_connect (r->GoingAway, boost::bind (&AudioStreamView::remove_region_view, this, boost::weak_ptr<Region> (r)));
 
 	RegionViewAdded (region_view);
 
@@ -200,9 +200,9 @@ AudioStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wai
 void
 AudioStreamView::remove_region_view (boost::weak_ptr<Region> weak_r)
 {
-	cerr << this << " RRV entry\n";
+	ENSURE_GUI_THREAD (*this, &AudioStreamView::remove_region_view, weak_r);
 
-	ENSURE_GUI_THREAD (*this, &AudioStreamView::remove_region_view, weak_r)
+	cerr << "a region went way, it appears to be ours (" << this << ")\n";
 
 	boost::shared_ptr<Region> r (weak_r.lock());
 
@@ -210,9 +210,7 @@ AudioStreamView::remove_region_view (boost::weak_ptr<Region> weak_r)
 		return;
 	}
 
-	cerr << this << " RRV action for  " << r << endl;
-
-	if (!_trackview.session().deletion_in_progress()) {
+	if (!_trackview.session()->deletion_in_progress()) {
 
 		for (CrossfadeViewList::iterator i = crossfade_views.begin(); i != crossfade_views.end();) {
 			CrossfadeViewList::iterator tmp;
@@ -286,9 +284,9 @@ AudioStreamView::playlist_changed (boost::shared_ptr<Diskstream> ds)
 	StreamView::playlist_changed(ds);
 
 	boost::shared_ptr<AudioPlaylist> apl = boost::dynamic_pointer_cast<AudioPlaylist>(ds->playlist());
+
 	if (apl) {
-		playlist_connections.push_back (apl->NewCrossfade.connect (
-				sigc::mem_fun (*this, &AudioStreamView::add_crossfade)));
+		playlist_connections.add_connection (apl->NewCrossfade.connect (boost::bind (&AudioStreamView::add_crossfade, this, _1)));
 	}
 }
 
@@ -349,7 +347,7 @@ AudioStreamView::add_crossfade (boost::shared_ptr<Crossfade> crossfade)
 	cv->set_valid (true);
 	crossfade->Invalidated.connect (sigc::mem_fun (*this, &AudioStreamView::remove_crossfade));
 	crossfade_views[cv->crossfade] = cv;
-	if (!_trackview.session().config.get_xfades_visible() || !crossfades_visible) {
+	if (!_trackview.session()->config.get_xfades_visible() || !crossfades_visible) {
 		cv->hide ();
 	}
 
@@ -462,12 +460,12 @@ AudioStreamView::setup_rec_box ()
 {
 	//cerr << _trackview.name() << " streamview SRB region_views.size() = " << region_views.size() << endl;
 
-	if (_trackview.session().transport_rolling()) {
+	if (_trackview.session()->transport_rolling()) {
 
 		// cerr << "\trolling\n";
 
 		if (!rec_active &&
-		    _trackview.session().record_status() == Session::Recording &&
+		    _trackview.session()->record_status() == Session::Recording &&
 		    _trackview.get_diskstream()->record_enabled()) {
 			if (_trackview.audio_track()->mode() == Normal && use_rec_regions && rec_regions.size() == rec_rects.size()) {
 
@@ -475,12 +473,7 @@ AudioStreamView::setup_rec_box ()
 
 				SourceList sources;
 
-				for (list<sigc::connection>::iterator prc = rec_data_ready_connections.begin();
-						prc != rec_data_ready_connections.end(); ++prc) {
-					(*prc).disconnect();
-				}
-				rec_data_ready_connections.clear();
-
+				rec_data_ready_connections.drop_connections ();
 				boost::shared_ptr<AudioDiskstream> ads = _trackview.audio_track()->audio_diskstream();
 
 				for (uint32_t n=0; n < ads->n_channels().n_audio(); ++n) {
@@ -488,9 +481,9 @@ AudioStreamView::setup_rec_box ()
 					if (src) {
 						sources.push_back (src);
 
-						rec_data_ready_connections.push_back (src->PeakRangeReady.connect (sigc::bind
-							(sigc::mem_fun (*this, &AudioStreamView::rec_peak_range_ready),
-							 boost::weak_ptr<Source>(src))));
+						rec_data_ready_connections.add_connection 
+							(src->PeakRangeReady.connect 
+							 (boost::bind (&AudioStreamView::rec_peak_range_ready, this, _1, _2, boost::weak_ptr<Source>(src))));
 					}
 				}
 
@@ -506,7 +499,7 @@ AudioStreamView::setup_rec_box ()
 						RegionFactory::create (sources, start, 1, "", 0, Region::DefaultFlags, false)));
 				assert(region);
 				region->block_property_changes ();
-				region->set_position (_trackview.session().transport_frame(), this);
+				region->set_position (_trackview.session()->transport_frame(), this);
 				rec_regions.push_back (make_pair(region, (RegionView*)0));
 			}
 
@@ -550,7 +543,7 @@ AudioStreamView::setup_rec_box ()
 
 			RecBoxInfo recbox;
 			recbox.rectangle = rec_rect;
-			recbox.start = _trackview.session().transport_frame();
+			recbox.start = _trackview.session()->transport_frame();
 			recbox.length = 0;
 
 			rec_rects.push_back (recbox);
@@ -562,7 +555,7 @@ AudioStreamView::setup_rec_box ()
 			rec_active = true;
 
 		} else if (rec_active &&
-			   (_trackview.session().record_status() != Session::Recording ||
+			   (_trackview.session()->record_status() != Session::Recording ||
 			    !_trackview.get_diskstream()->record_enabled())) {
 			screen_update_connection.disconnect();
 			rec_active = false;
@@ -577,13 +570,7 @@ AudioStreamView::setup_rec_box ()
 
 			/* disconnect rapid update */
 			screen_update_connection.disconnect();
-
-			for (list<sigc::connection>::iterator prc = rec_data_ready_connections.begin();
-					prc != rec_data_ready_connections.end(); ++prc) {
-				(*prc).disconnect();
-			}
-			rec_data_ready_connections.clear();
-
+			rec_data_ready_connections.drop_connections ();
 			rec_updating = false;
 			rec_active = false;
 
diff --git a/gtk2_ardour/audio_time_axis.cc b/gtk2_ardour/audio_time_axis.cc
index f9c10a3894..040e56a323 100644
--- a/gtk2_ardour/audio_time_axis.cc
+++ b/gtk2_ardour/audio_time_axis.cc
@@ -76,7 +76,7 @@ using namespace PBD;
 using namespace Gtk;
 using namespace Editing;
 
-AudioTimeAxisView::AudioTimeAxisView (PublicEditor& ed, Session& sess, boost::shared_ptr<Route> rt, Canvas& canvas)
+AudioTimeAxisView::AudioTimeAxisView (PublicEditor& ed, Session* sess, boost::shared_ptr<Route> rt, Canvas& canvas)
 	: AxisView(sess)
 	, RouteTimeAxisView(ed, sess, rt, canvas)
 {
diff --git a/gtk2_ardour/audio_time_axis.h b/gtk2_ardour/audio_time_axis.h
index 02c7ed4f19..80450e9f61 100644
--- a/gtk2_ardour/audio_time_axis.h
+++ b/gtk2_ardour/audio_time_axis.h
@@ -66,7 +66,7 @@ class AutomationTimeAxisView;
 class AudioTimeAxisView : public RouteTimeAxisView
 {
   public:
- 	AudioTimeAxisView (PublicEditor&, ARDOUR::Session&, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
+ 	AudioTimeAxisView (PublicEditor&, ARDOUR::Session*, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
  	virtual ~AudioTimeAxisView ();
 
 	AudioStreamView* audio_view();
diff --git a/gtk2_ardour/automation_line.cc b/gtk2_ardour/automation_line.cc
index f56ca898ce..7f9bd6b455 100644
--- a/gtk2_ardour/automation_line.cc
+++ b/gtk2_ardour/automation_line.cc
@@ -87,7 +87,7 @@ AutomationLine::AutomationLine (const string& name, TimeAxisView& tv, ArdourCanv
 
 	alist->StateChanged.connect (sigc::mem_fun(*this, &AutomationLine::list_changed));
 
-	trackview.session().register_with_memento_command_factory(alist->id(), this);
+	trackview.session()->register_with_memento_command_factory(alist->id(), this);
 
 	if (alist->parameter().type() == GainAutomation ||
 	    alist->parameter().type() == EnvelopeAutomation) {
@@ -215,8 +215,8 @@ AutomationLine::modify_point_y (ControlPoint& cp, double y)
 
 	double const x = trackview.editor().frame_to_unit (_time_converter.to((*cp.model())->when));
 
-	trackview.editor().current_session()->begin_reversible_command (_("automation event move"));
-	trackview.editor().current_session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &get_state(), 0));
+	trackview.editor().session()->begin_reversible_command (_("automation event move"));
+	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &get_state(), 0));
 
 	cp.move_to (x, y, ControlPoint::Full);
 	reset_line_coords (cp);
@@ -231,9 +231,9 @@ AutomationLine::modify_point_y (ControlPoint& cp, double y)
 
 	update_pending = false;
 
-	trackview.editor().current_session()->add_command (new MementoCommand<AutomationList>(*alist.get(), 0, &alist->get_state()));
-	trackview.editor().current_session()->commit_reversible_command ();
-	trackview.editor().current_session()->set_dirty ();
+	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), 0, &alist->get_state()));
+	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().session()->set_dirty ();
 }
 
 
@@ -723,7 +723,7 @@ AutomationLine::invalidate_point (ALPoints& p, uint32_t index)
 void
 AutomationLine::start_drag (ControlPoint* cp, nframes_t x, float fraction)
 {
-	if (trackview.editor().current_session() == 0) { /* how? */
+	if (trackview.editor().session() == 0) { /* how? */
 		return;
 	}
 
@@ -735,8 +735,8 @@ AutomationLine::start_drag (ControlPoint* cp, nframes_t x, float fraction)
 		str = _("automation range drag");
 	}
 
-	trackview.editor().current_session()->begin_reversible_command (str);
-	trackview.editor().current_session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &get_state(), 0));
+	trackview.editor().session()->begin_reversible_command (str);
+	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &get_state(), 0));
 
 	drag_x = x;
 	drag_distance = 0;
@@ -830,9 +830,9 @@ AutomationLine::end_drag (ControlPoint* cp)
 
 	update_pending = false;
 
-	trackview.editor().current_session()->add_command (new MementoCommand<AutomationList>(*alist.get(), 0, &alist->get_state()));
-	trackview.editor().current_session()->commit_reversible_command ();
-	trackview.editor().current_session()->set_dirty ();
+	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), 0, &alist->get_state()));
+	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().session()->set_dirty ();
 }
 
 
@@ -973,15 +973,15 @@ AutomationLine::remove_point (ControlPoint& cp)
 
 	model_representation (cp, mr);
 
-	trackview.editor().current_session()->begin_reversible_command (_("remove control point"));
+	trackview.editor().session()->begin_reversible_command (_("remove control point"));
 	XMLNode &before = alist->get_state();
 
 	alist->erase (mr.start, mr.end);
 
-	trackview.editor().current_session()->add_command(new MementoCommand<AutomationList>(
+	trackview.editor().session()->add_command(new MementoCommand<AutomationList>(
 			*alist.get(), &before, &alist->get_state()));
-	trackview.editor().current_session()->commit_reversible_command ();
-	trackview.editor().current_session()->set_dirty ();
+	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().session()->set_dirty ();
 }
 
 void
@@ -1020,7 +1020,7 @@ AutomationLine::get_selectables (nframes_t& start, nframes_t& end,
 
 				if (collecting) {
 
-					results.push_back (new AutomationSelectable (nstart, nend, botfrac, topfrac, trackview));
+					results.push_back (new AutomationSelectable (nstart, nend, botfrac, topfrac, &trackview));
 					collecting = false;
 					nstart = max_frames;
 					nend = 0;
@@ -1030,7 +1030,7 @@ AutomationLine::get_selectables (nframes_t& start, nframes_t& end,
 	}
 
 	if (collecting) {
-		results.push_back (new AutomationSelectable (nstart, nend, botfrac, topfrac, trackview));
+		results.push_back (new AutomationSelectable (nstart, nend, botfrac, topfrac, &trackview));
 	}
 
 }
@@ -1057,7 +1057,7 @@ AutomationLine::set_selected_points (PointSelection& points)
 
 	for (PointSelection::iterator r = points.begin(); r != points.end(); ++r) {
 
-		if (&(*r).track != &trackview) {
+		if ((*r).track != &trackview) {
 			continue;
 		}
 
@@ -1190,10 +1190,10 @@ AutomationLine::clear ()
 	/* parent must create command */
 	XMLNode &before = get_state();
 	alist->clear();
-	trackview.editor().current_session()->add_command (
+	trackview.editor().session()->add_command (
 			new MementoCommand<AutomationLine>(*this, &before, &get_state()));
-	trackview.editor().current_session()->commit_reversible_command ();
-	trackview.editor().current_session()->set_dirty ();
+	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().session()->set_dirty ();
 }
 
 void
diff --git a/gtk2_ardour/automation_line.h b/gtk2_ardour/automation_line.h
index c8c265c307..c16bf60008 100644
--- a/gtk2_ardour/automation_line.h
+++ b/gtk2_ardour/automation_line.h
@@ -52,7 +52,7 @@ namespace Gnome {
 	}
 }
 
-class AutomationLine : public sigc::trackable, public PBD::StatefulThingWithGoingAway
+class AutomationLine : public sigc::trackable, public PBD::StatefulDestructible
 {
   public:
 	AutomationLine (const std::string& name, TimeAxisView&, ArdourCanvas::Group&,
diff --git a/gtk2_ardour/automation_region_view.cc b/gtk2_ardour/automation_region_view.cc
index a891feb2e1..9056adc693 100644
--- a/gtk2_ardour/automation_region_view.cc
+++ b/gtk2_ardour/automation_region_view.cc
@@ -117,16 +117,16 @@ AutomationRegionView::add_automation_event (GdkEvent* /*event*/, nframes_t when,
 
 	_line->view_to_model_coord (x, y);
 
-	view->session().begin_reversible_command (_("add automation event"));
+	view->session()->begin_reversible_command (_("add automation event"));
 	XMLNode& before = _line->the_list()->get_state();
 
 	_line->the_list()->add (x, y);
 
 	XMLNode& after = _line->the_list()->get_state();
-	view->session().commit_reversible_command (new MementoCommand<ARDOUR::AutomationList>(
+	view->session()->commit_reversible_command (new MementoCommand<ARDOUR::AutomationList>(
 			*_line->the_list(), &before, &after));
 
-	view->session().set_dirty ();
+	view->session()->set_dirty ();
 }
 
 void
diff --git a/gtk2_ardour/automation_selectable.h b/gtk2_ardour/automation_selectable.h
index 851da8bf79..92e73a3c33 100644
--- a/gtk2_ardour/automation_selectable.h
+++ b/gtk2_ardour/automation_selectable.h
@@ -31,17 +31,17 @@ struct AutomationSelectable : public Selectable
     nframes_t end;
     double low_fract;
     double high_fract;
-    TimeAxisView& track;
+    TimeAxisView* track; // ref would be better, but ARDOUR::SessionHandlePtr is non-assignable
 
-    AutomationSelectable (nframes_t s, nframes_t e, double l, double h, TimeAxisView& atv)
+    AutomationSelectable (nframes_t s, nframes_t e, double l, double h, TimeAxisView* atv)
 	    : start (s), end (e), low_fract (l), high_fract (h), track (atv) {}
 
     bool operator== (const AutomationSelectable& other) {
 	    return start == other.start &&
-		    end == other.end &&
-		    low_fract == other.low_fract &&
-		    high_fract == other.high_fract &&
-		    &track == &other.track;
+	    end == other.end &&
+	    low_fract == other.low_fract &&
+	    high_fract == other.high_fract &&
+	    track == other.track;
     }
 };
 
diff --git a/gtk2_ardour/automation_streamview.cc b/gtk2_ardour/automation_streamview.cc
index a22b2644d0..9c7cf50ac7 100644
--- a/gtk2_ardour/automation_streamview.cc
+++ b/gtk2_ardour/automation_streamview.cc
@@ -129,7 +129,7 @@ AutomationStreamView::add_region_view_internal (boost::shared_ptr<Region> region
 	display_region(region_view);
 
 	/* catch regionview going away */
-	region->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &AutomationStreamView::remove_region_view), region));
+	scoped_connect (region->GoingAway, boost::bind (&AutomationStreamView::remove_region_view, this, boost::weak_ptr<Region>(region)));
 
 	RegionViewAdded (region_view);
 
diff --git a/gtk2_ardour/automation_time_axis.cc b/gtk2_ardour/automation_time_axis.cc
index 3184033dca..aee9b70726 100644
--- a/gtk2_ardour/automation_time_axis.cc
+++ b/gtk2_ardour/automation_time_axis.cc
@@ -58,7 +58,7 @@ const string AutomationTimeAxisView::state_node_name = "AutomationChild";
  * For route child (e.g. plugin) automation, pass the child for \a.
  * For region automation (e.g. MIDI CC), pass null for \a.
  */
-AutomationTimeAxisView::AutomationTimeAxisView (Session& s, boost::shared_ptr<Route> r,
+AutomationTimeAxisView::AutomationTimeAxisView (Session* s, boost::shared_ptr<Route> r,
 		boost::shared_ptr<Automatable> a, boost::shared_ptr<AutomationControl> c,
 		PublicEditor& e, TimeAxisView& parent, bool show_regions,
 		ArdourCanvas::Canvas& canvas, const string & nom, const string & nomparent)
@@ -370,11 +370,11 @@ AutomationTimeAxisView::set_interpolation (AutomationList::InterpolationStyle st
 void
 AutomationTimeAxisView::clear_clicked ()
 {
-	_session.begin_reversible_command (_("clear automation"));
+	_session->begin_reversible_command (_("clear automation"));
 	if (_line) {
 		_line->clear ();
 	}
-	_session.commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -587,15 +587,15 @@ AutomationTimeAxisView::add_automation_event (ArdourCanvas::Item* /*item*/, GdkE
 
 	_line->view_to_model_coord (x, y);
 
-	_session.begin_reversible_command (_("add automation event"));
+	_session->begin_reversible_command (_("add automation event"));
 	XMLNode& before = _control->alist()->get_state();
 
 	_control->alist()->add (when, y);
 
 	XMLNode& after = _control->alist()->get_state();
-	_session.commit_reversible_command (new MementoCommand<ARDOUR::AutomationList>(*_control->alist(), &before, &after));
+	_session->commit_reversible_command (new MementoCommand<ARDOUR::AutomationList>(*_control->alist(), &before, &after));
 
-	_session.set_dirty ();
+	_session->set_dirty ();
 }
 
 bool
@@ -617,7 +617,7 @@ AutomationTimeAxisView::cut_copy_clear_one (AutomationLine& line, Selection& sel
 	case Cut:
 		if ((what_we_got = alist->cut (selection.time.front().start, selection.time.front().end)) != 0) {
 			_editor.get_cut_buffer().add (what_we_got);
-			_session.add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
+			_session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
 			ret = true;
 		}
 		break;
@@ -629,7 +629,7 @@ AutomationTimeAxisView::cut_copy_clear_one (AutomationLine& line, Selection& sel
 
 	case Clear:
 		if ((what_we_got = alist->cut (selection.time.front().start, selection.time.front().end)) != 0) {
-			_session.add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
+			_session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
 			ret = true;
 		}
 		break;
@@ -659,11 +659,11 @@ AutomationTimeAxisView::reset_objects_one (AutomationLine& line, PointSelection&
 {
 	boost::shared_ptr<AutomationList> alist(line.the_list());
 
-	_session.add_command (new MementoCommand<AutomationList>(*alist.get(), &alist->get_state(), 0));
+	_session->add_command (new MementoCommand<AutomationList>(*alist.get(), &alist->get_state(), 0));
 
 	for (PointSelection::iterator i = selection.begin(); i != selection.end(); ++i) {
 
-		if (&(*i).track != this) {
+		if ((*i).track != this) {
 			continue;
 		}
 
@@ -688,7 +688,7 @@ AutomationTimeAxisView::cut_copy_clear_objects_one (AutomationLine& line, PointS
 
 	for (PointSelection::iterator i = selection.begin(); i != selection.end(); ++i) {
 
-		if (&(*i).track != this) {
+		if ((*i).track != this) {
 			continue;
 		}
 
@@ -696,7 +696,7 @@ AutomationTimeAxisView::cut_copy_clear_objects_one (AutomationLine& line, PointS
 		case Cut:
 			if ((what_we_got = alist->cut ((*i).start, (*i).end)) != 0) {
 				_editor.get_cut_buffer().add (what_we_got);
-				_session.add_command (new MementoCommand<AutomationList>(*alist.get(), new XMLNode (before), &alist->get_state()));
+				_session->add_command (new MementoCommand<AutomationList>(*alist.get(), new XMLNode (before), &alist->get_state()));
 				ret = true;
 			}
 			break;
@@ -708,7 +708,7 @@ AutomationTimeAxisView::cut_copy_clear_objects_one (AutomationLine& line, PointS
 
 		case Clear:
 			if ((what_we_got = alist->cut ((*i).start, (*i).end)) != 0) {
-				_session.add_command (new MementoCommand<AutomationList>(*alist.get(), new XMLNode (before), &alist->get_state()));
+				_session->add_command (new MementoCommand<AutomationList>(*alist.get(), new XMLNode (before), &alist->get_state()));
 				ret = true;
 			}
 			break;
@@ -765,7 +765,7 @@ AutomationTimeAxisView::paste_one (AutomationLine& line, nframes_t pos, float ti
 
 	XMLNode &before = alist->get_state();
 	alist->paste (copy, pos, times);
-	_session.add_command (new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
+	_session->add_command (new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
 
 	return true;
 }
@@ -834,7 +834,7 @@ AutomationTimeAxisView::add_line (boost::shared_ptr<AutomationLine> line)
 	assert(line->the_list() == _control->list());
 
 	automation_connection = _control->alist()->automation_state_changed.connect
-		(sigc::mem_fun(*this, &AutomationTimeAxisView::automation_state_changed));
+		(boost::bind (&AutomationTimeAxisView::automation_state_changed, this));
 
 	_line = line;
 	//_controller = AutomationController::create(_session, line->the_list(), _control);
diff --git a/gtk2_ardour/automation_time_axis.h b/gtk2_ardour/automation_time_axis.h
index f4d71f93c2..f00d0a24fe 100644
--- a/gtk2_ardour/automation_time_axis.h
+++ b/gtk2_ardour/automation_time_axis.h
@@ -54,7 +54,7 @@ class AutomationController;
 
 class AutomationTimeAxisView : public TimeAxisView {
   public:
-	AutomationTimeAxisView (ARDOUR::Session&,
+	AutomationTimeAxisView (ARDOUR::Session*,
 				boost::shared_ptr<ARDOUR::Route>,
 				boost::shared_ptr<ARDOUR::Automatable>,
 				boost::shared_ptr<ARDOUR::AutomationControl>,
@@ -151,7 +151,7 @@ class AutomationTimeAxisView : public TimeAxisView {
 	void set_interpolation (ARDOUR::AutomationList::InterpolationStyle);
 	void interpolation_changed ();
 
-	sigc::connection automation_connection;
+	boost::signals2::scoped_connection automation_connection;
 
 	void update_extra_xml_shown (bool editor_shown);
 
diff --git a/gtk2_ardour/axis_view.cc b/gtk2_ardour/axis_view.cc
index bed5e098b0..d645a51873 100644
--- a/gtk2_ardour/axis_view.cc
+++ b/gtk2_ardour/axis_view.cc
@@ -41,10 +41,12 @@
 using namespace std;
 using namespace Gtk;
 using namespace Gtkmm2ext;
+using namespace ARDOUR;
 
 list<Gdk::Color> AxisView::used_colors;
 
-AxisView::AxisView (ARDOUR::Session& sess) : _session(sess)
+AxisView::AxisView (ARDOUR::Session* sess) 
+	: SessionHandlePtr (sess)
 {
 	_selected = false;
 	_marked_for_display = false;
diff --git a/gtk2_ardour/axis_view.h b/gtk2_ardour/axis_view.h
index 21220d5439..3d2591a977 100644
--- a/gtk2_ardour/axis_view.h
+++ b/gtk2_ardour/axis_view.h
@@ -26,6 +26,10 @@
 #include <gdkmm/color.h>
 
 #include "pbd/xml++.h"
+#include "pbd/destructible.h"
+
+#include "ardour/session_handle.h"
+
 #include "prompter.h"
 #include "selectable.h"
 
@@ -37,7 +41,7 @@ namespace ARDOUR {
  * AxisView defines the abstract base class for time-axis trackviews and routes.
  *
  */
-class AxisView : public virtual Selectable
+class AxisView : public virtual Selectable, public PBD::Destructible, public PBD::ScopedConnectionList, public ARDOUR::SessionHandlePtr
 {
   public:
 	/**
@@ -47,7 +51,7 @@ class AxisView : public virtual Selectable
 	 */
 	Gdk::Color color() const { return _color; }
 
-	ARDOUR::Session& session() const { return _session; }
+	ARDOUR::Session* session() const { return _session; }
 
 	virtual std::string name() const = 0;
 
@@ -57,17 +61,15 @@ class AxisView : public virtual Selectable
 	}
 
 	sigc::signal<void> Hiding;
-	sigc::signal<void> GoingAway;
 
 	void set_old_order_key (uint32_t ok) { _old_order_key = ok; }
 	uint32_t old_order_key() const { return _old_order_key; }
 
   protected:
 
-	AxisView (ARDOUR::Session& sess);
+	AxisView (ARDOUR::Session* sess);
 	virtual ~AxisView();
 
-
 	/**
 	 * Generate a new random TrackView color, unique from those colors already used.
 	 *
@@ -76,7 +78,6 @@ class AxisView : public virtual Selectable
 	static Gdk::Color unique_random_color();
 
 
-	ARDOUR::Session& _session;
 	Gdk::Color _color;
 
 	static std::list<Gdk::Color> used_colors;
diff --git a/gtk2_ardour/bundle_manager.cc b/gtk2_ardour/bundle_manager.cc
index b638544836..ca047ebea0 100644
--- a/gtk2_ardour/bundle_manager.cc
+++ b/gtk2_ardour/bundle_manager.cc
@@ -34,11 +34,9 @@
 using namespace std;
 using namespace ARDOUR;
 
-BundleEditorMatrix::BundleEditorMatrix (
-	Gtk::Window* parent, Session* session, boost::shared_ptr<Bundle> bundle
-	)
-	: PortMatrix (parent, session, bundle->type()),
-	  _bundle (bundle)
+BundleEditorMatrix::BundleEditorMatrix (Gtk::Window* parent, Session* session, boost::shared_ptr<Bundle> bundle)
+	: PortMatrix (parent, session, bundle->type())
+	, _bundle (bundle)
 {
 	_port_group = boost::shared_ptr<PortGroup> (new PortGroup (""));
 	_port_group->add_bundle (_bundle);
@@ -285,8 +283,12 @@ BundleEditor::on_map ()
 
 
 BundleManager::BundleManager (Session* session)
-	: ArdourDialog (_("Bundle Manager")), _session (session), edit_button (_("Edit")), delete_button (_("Delete"))
+	: ArdourDialog (_("Bundle Manager"))
+	, edit_button (_("Edit"))
+	, delete_button (_("Delete"))
 {
+	set_session (session);
+
 	_list_model = Gtk::ListStore::create (_list_model_columns);
 	_tree_view.set_model (_list_model);
 	_tree_view.append_column (_("Name"), _list_model_columns.name);
diff --git a/gtk2_ardour/bundle_manager.h b/gtk2_ardour/bundle_manager.h
index 3beb77e952..d064e40bf6 100644
--- a/gtk2_ardour/bundle_manager.h
+++ b/gtk2_ardour/bundle_manager.h
@@ -115,7 +115,6 @@ class BundleManager : public ArdourDialog
 	Gtk::TreeView _tree_view;
 	Glib::RefPtr<Gtk::ListStore> _list_model;
 	ModelColumns _list_model_columns;
-	ARDOUR::Session* _session;
 	Gtk::Button edit_button;
 	Gtk::Button delete_button;
 };
diff --git a/gtk2_ardour/crossfade_edit.cc b/gtk2_ardour/crossfade_edit.cc
index 4c9b8b7537..7a7b740a25 100644
--- a/gtk2_ardour/crossfade_edit.cc
+++ b/gtk2_ardour/crossfade_edit.cc
@@ -72,10 +72,9 @@ CrossfadeEditor::Half::Half ()
 {
 }
 
-CrossfadeEditor::CrossfadeEditor (Session& s, boost::shared_ptr<Crossfade> xf, double my, double mxy)
+CrossfadeEditor::CrossfadeEditor (Session* s, boost::shared_ptr<Crossfade> xf, double my, double mxy)
 	: ArdourDialog (_("ardour: x-fade edit")),
 	  xfade (xf),
-	  session (s),
 	  clear_button (_("Clear")),
 	  revert_button (_("Reset")),
 	  audition_both_button (_("Fade")),
@@ -96,6 +95,8 @@ CrossfadeEditor::CrossfadeEditor (Session& s, boost::shared_ptr<Crossfade> xf, d
 	  select_in_button (_("Fade In")),
 	  select_out_button (_("Fade Out"))
 {
+	set_session (s);
+
 	set_wmclass (X_("ardour_automationedit"), "Ardour");
 	set_name ("CrossfadeEditWindow");
 	set_position (Gtk::WIN_POS_MOUSE);
@@ -292,7 +293,7 @@ CrossfadeEditor::CrossfadeEditor (Session& s, boost::shared_ptr<Crossfade> xf, d
 
 	xfade->StateChanged.connect (sigc::mem_fun(*this, &CrossfadeEditor::xfade_changed));
 
-	session.AuditionActive.connect (sigc::mem_fun(*this, &CrossfadeEditor::audition_state_changed));
+	_session_connections.add_connection (_session->AuditionActive.connect (sigc::mem_fun(*this, &CrossfadeEditor::audition_state_changed)));
 	show_all_children();
 }
 
@@ -1129,7 +1130,7 @@ CrossfadeEditor::make_waves (boost::shared_ptr<AudioRegion> region, WhichFade wh
 
 		gdouble yoff = n * ht;
 
-		if (region->audio_source(n)->peaks_ready (sigc::bind (sigc::mem_fun(*this, &CrossfadeEditor::peaks_ready), region, which), peaks_ready_connection)) {
+		if (region->audio_source(n)->peaks_ready (boost::bind (&CrossfadeEditor::peaks_ready, this, boost::weak_ptr<AudioRegion>(region), which), peaks_ready_connection)) {
 			WaveView* waveview = new WaveView (*(canvas->root()));
 
 			waveview->property_data_src() = region.get();
@@ -1163,8 +1164,14 @@ CrossfadeEditor::make_waves (boost::shared_ptr<AudioRegion> region, WhichFade wh
 }
 
 void
-CrossfadeEditor::peaks_ready (boost::shared_ptr<AudioRegion> r, WhichFade which)
+CrossfadeEditor::peaks_ready (boost::weak_ptr<AudioRegion> wr, WhichFade which)
 {
+	boost::shared_ptr<AudioRegion> r (wr.lock());
+
+	if (!r) {
+		return;
+	}
+
 	/* this should never be called, because the peak files for an xfade
 	   will be ready by the time we want them. but our API forces us
 	   to provide this, so ..
@@ -1176,7 +1183,7 @@ CrossfadeEditor::peaks_ready (boost::shared_ptr<AudioRegion> r, WhichFade which)
 void
 CrossfadeEditor::audition (Audition which)
 {
-	AudioPlaylist& pl (session.the_auditioner()->prepare_playlist());
+	AudioPlaylist& pl (_session->the_auditioner()->prepare_playlist());
 	nframes_t preroll;
 	nframes_t postroll;
 	nframes_t left_start_offset;
@@ -1184,13 +1191,13 @@ CrossfadeEditor::audition (Audition which)
 	nframes_t left_length;
 
 	if (which != Right && preroll_button.get_active()) {
-		preroll = session.frame_rate() * 2;  //2 second hardcoded preroll for now
+		preroll = _session->frame_rate() * 2;  //2 second hardcoded preroll for now
 	} else {
 		preroll = 0;
 	}
 
 	if (which != Left && postroll_button.get_active()) {
-		postroll = session.frame_rate() * 2;  //2 second hardcoded postroll for now
+		postroll = _session->frame_rate() * 2;  //2 second hardcoded postroll for now
 	} else {
 		postroll = 0;
 	}
@@ -1220,9 +1227,9 @@ CrossfadeEditor::audition (Audition which)
 
 	//apply a 20ms declicking fade at the start and end of auditioning
 	left->set_fade_in_active(true);
-	left->set_fade_in_length(session.frame_rate() / 50);
+	left->set_fade_in_length(_session->frame_rate() / 50);
 	right->set_fade_out_active(true);
-	right->set_fade_out_length(session.frame_rate() / 50);
+	right->set_fade_out_length(_session->frame_rate() / 50);
 
 	pl.add_region (left, 0);
 	pl.add_region (right, 1 + preroll);
@@ -1236,7 +1243,7 @@ CrossfadeEditor::audition (Audition which)
 	/* there is only one ... */
 	pl.foreach_crossfade (sigc::mem_fun (*this, &CrossfadeEditor::setup));
 
-	session.audition_playlist ();
+	_session->audition_playlist ();
 }
 
 void
@@ -1251,7 +1258,7 @@ CrossfadeEditor::audition_left_dry ()
 	boost::shared_ptr<AudioRegion> left (boost::dynamic_pointer_cast<AudioRegion> (RegionFactory::create (xfade->out(), xfade->out()->length() - xfade->length(), xfade->length(), "xfade left",
 													      0, Region::DefaultFlags, false)));
 
-	session.audition_region (left);
+	_session->audition_region (left);
 }
 
 void
@@ -1265,7 +1272,7 @@ CrossfadeEditor::audition_right_dry ()
 {
 	boost::shared_ptr<AudioRegion> right (boost::dynamic_pointer_cast<AudioRegion> (RegionFactory::create (xfade->in(), 0, xfade->length(), "xfade in",
 													       0, Region::DefaultFlags, false)));
-	session.audition_region (right);
+	_session->audition_region (right);
 }
 
 void
@@ -1277,7 +1284,7 @@ CrossfadeEditor::audition_right ()
 void
 CrossfadeEditor::cancel_audition ()
 {
-	session.cancel_audition ();
+	_session->cancel_audition ();
 }
 
 void
@@ -1285,7 +1292,7 @@ CrossfadeEditor::audition_toggled ()
 {
 	bool x;
 
-	if ((x = audition_both_button.get_active ()) != session.is_auditioning()) {
+	if ((x = audition_both_button.get_active ()) != _session->is_auditioning()) {
 
 		if (x) {
 			audition_both ();
@@ -1300,7 +1307,7 @@ CrossfadeEditor::audition_right_toggled ()
 {
 	bool x;
 
-	if ((x = audition_right_button.get_active ()) != session.is_auditioning()) {
+	if ((x = audition_right_button.get_active ()) != _session->is_auditioning()) {
 
 		if (x) {
 			audition_right ();
@@ -1315,7 +1322,7 @@ CrossfadeEditor::audition_right_dry_toggled ()
 {
 	bool x;
 
-	if ((x = audition_right_dry_button.get_active ()) != session.is_auditioning()) {
+	if ((x = audition_right_dry_button.get_active ()) != _session->is_auditioning()) {
 
 		if (x) {
 			audition_right_dry ();
@@ -1330,7 +1337,7 @@ CrossfadeEditor::audition_left_toggled ()
 {
 	bool x;
 
-	if ((x = audition_left_button.get_active ()) != session.is_auditioning()) {
+	if ((x = audition_left_button.get_active ()) != _session->is_auditioning()) {
 
 		if (x) {
 			audition_left ();
@@ -1345,7 +1352,7 @@ CrossfadeEditor::audition_left_dry_toggled ()
 {
 	bool x;
 
-	if ((x = audition_left_dry_button.get_active ()) != session.is_auditioning()) {
+	if ((x = audition_left_dry_button.get_active ()) != _session->is_auditioning()) {
 
 		if (x) {
 			audition_left_dry ();
@@ -1382,7 +1389,7 @@ CrossfadeEditor::on_key_release_event (GdkEventKey* ev)
 		break;
 
 	case GDK_space:
-		if (session.is_auditioning()) {
+		if (_session->is_auditioning()) {
 			cancel_audition ();
 		} else {
 			audition_both_button.set_active (!audition_both_button.get_active());
diff --git a/gtk2_ardour/crossfade_edit.h b/gtk2_ardour/crossfade_edit.h
index f2ec1a125b..7334002abd 100644
--- a/gtk2_ardour/crossfade_edit.h
+++ b/gtk2_ardour/crossfade_edit.h
@@ -27,6 +27,8 @@
 #include <gtkmm/radiobutton.h>
 
 #include "evoral/Curve.hpp"
+#include "ardour/session_handle.h"
+
 #include "ardour_dialog.h"
 #include "canvas.h"
 
@@ -40,7 +42,7 @@ namespace ARDOUR
 class CrossfadeEditor : public ArdourDialog
 {
   public:
-	CrossfadeEditor (ARDOUR::Session&, boost::shared_ptr<ARDOUR::Crossfade>, double miny, double maxy);
+	CrossfadeEditor (ARDOUR::Session*, boost::shared_ptr<ARDOUR::Crossfade>, double miny, double maxy);
 	~CrossfadeEditor ();
 
 	void apply ();
@@ -79,7 +81,6 @@ class CrossfadeEditor : public ArdourDialog
 
   private:
 	boost::shared_ptr<ARDOUR::Crossfade> xfade;
-	ARDOUR::Session& session;
 
 	Gtk::VBox vpacker;
 
@@ -182,10 +183,10 @@ class CrossfadeEditor : public ArdourDialog
 
 	void set (const ARDOUR::AutomationList& alist, WhichFade);
 
-	sigc::connection peaks_ready_connection;
+	boost::signals2::scoped_connection peaks_ready_connection;
 
 	void make_waves (boost::shared_ptr<ARDOUR::AudioRegion>, WhichFade);
-	void peaks_ready (boost::shared_ptr<ARDOUR::AudioRegion> r, WhichFade);
+	void peaks_ready (boost::weak_ptr<ARDOUR::AudioRegion> r, WhichFade);
 
 	void _apply_to (boost::shared_ptr<ARDOUR::Crossfade> xf);
 	void setup (boost::shared_ptr<ARDOUR::Crossfade>);
diff --git a/gtk2_ardour/crossfade_view.cc b/gtk2_ardour/crossfade_view.cc
index 2df4cd0982..63868ca895 100644
--- a/gtk2_ardour/crossfade_view.cc
+++ b/gtk2_ardour/crossfade_view.cc
@@ -39,7 +39,7 @@ using namespace Editing;
 using namespace Gnome;
 using namespace Canvas;
 
-sigc::signal<void,CrossfadeView*> CrossfadeView::GoingAway;
+boost::signals2::signal<void(CrossfadeView*)> CrossfadeView::GoingAway;
 
 CrossfadeView::CrossfadeView (ArdourCanvas::Group *parent,
 			      RouteTimeAxisView &tv,
diff --git a/gtk2_ardour/crossfade_view.h b/gtk2_ardour/crossfade_view.h
index 3e4021742e..a82387393f 100644
--- a/gtk2_ardour/crossfade_view.h
+++ b/gtk2_ardour/crossfade_view.h
@@ -22,7 +22,7 @@
 
 #include <vector>
 #include <libgnomecanvasmm.h>
-#include <sigc++/signal.h>
+#include <boost/signals2.hpp>
 #include "ardour/crossfade.h"
 
 #include "time_axis_view_item.h"
@@ -52,7 +52,7 @@ struct CrossfadeView : public TimeAxisViewItem
     bool visible() const { return _visible; }
     void set_valid (bool yn);
 
-    static sigc::signal<void,CrossfadeView*> GoingAway;
+    static boost::signals2::signal<void(CrossfadeView*)> GoingAway;
 
     AudioRegionView& upper_regionview () const;
 
diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index dd9cdf9582..bf0b2124bb 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -268,7 +268,6 @@ Editor::Editor ()
 
 	PublicEditor::_instance = this;
 
-	session = 0;
 	_have_idled = false;
 
 	selection = new Selection (this);
@@ -628,7 +627,7 @@ Editor::Editor ()
 	_playlist_selector = new PlaylistSelector();
 	_playlist_selector->signal_delete_event().connect (sigc::bind (sigc::ptr_fun (just_hide_it), static_cast<Window *> (_playlist_selector)));
 
-	RegionView::RegionViewGoingAway.connect (sigc::mem_fun(*this, &Editor::catch_vanishing_regionview));
+	scoped_connect (RegionView::RegionViewGoingAway, boost::bind (&Editor::catch_vanishing_regionview, this, _1));
 
 	/* nudge stuff */
 
@@ -805,8 +804,8 @@ Editor::instant_save ()
 		return;
 	}
 
-	if (session) {
-		session->add_instant_xml(get_state());
+	if (_session) {
+		_session->add_instant_xml(get_state());
 	} else {
 		Config->add_instant_xml(get_state());
 	}
@@ -815,7 +814,7 @@ Editor::instant_save ()
 void
 Editor::zoom_adjustment_changed ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -824,8 +823,8 @@ Editor::zoom_adjustment_changed ()
 	if (fpu < 1.0) {
 		fpu = 1.0;
 		zoom_range_clock.set ((nframes64_t) floor (fpu * _canvas_width));
-	} else if (fpu > session->current_end_frame() / _canvas_width) {
-		fpu = session->current_end_frame() / _canvas_width;
+	} else if (fpu > _session->current_end_frame() / _canvas_width) {
+		fpu = _session->current_end_frame() / _canvas_width;
 		zoom_range_clock.set ((nframes64_t) floor (fpu * _canvas_width));
 	}
 
@@ -837,7 +836,7 @@ Editor::control_scroll (float fraction)
 {
 	ENSURE_GUI_THREAD (*this, &Editor::control_scroll, fraction)
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -855,7 +854,7 @@ Editor::control_scroll (float fraction)
 	*/
 
 	if (!_control_scroll_target) {
-		_control_scroll_target = session->transport_frame();
+		_control_scroll_target = _session->transport_frame();
 		_dragging_playhead = true;
 	}
 
@@ -897,7 +896,7 @@ Editor::control_scroll (float fraction)
 bool
 Editor::deferred_control_scroll (nframes64_t /*target*/)
 {
-	session->request_locate (*_control_scroll_target, session->transport_rolling());
+	_session->request_locate (*_control_scroll_target, _session->transport_rolling());
 	// reset for next stream
 	_control_scroll_target = boost::none;
 	_dragging_playhead = false;
@@ -907,7 +906,7 @@ Editor::deferred_control_scroll (nframes64_t /*target*/)
 void
 Editor::access_action (std::string action_group, std::string action_item)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -949,7 +948,7 @@ Editor::map_position_change (nframes64_t frame)
 {
 	ENSURE_GUI_THREAD (*this, &Editor::map_position_change, frame)
 
-	if (session == 0 || !_follow_playhead) {
+	if (_session == 0 || !_follow_playhead) {
 		return;
 	}
 
@@ -987,12 +986,12 @@ Editor::center_screen_internal (nframes64_t frame, float page)
 void
 Editor::handle_new_duration ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
 	ENSURE_GUI_THREAD (*this, &Editor::handle_new_duration)
-	nframes64_t new_end = session->current_end_frame() + (nframes64_t) floorf (current_page_frames() * 0.10f);
+	nframes64_t new_end = _session->current_end_frame() + (nframes64_t) floorf (current_page_frames() * 0.10f);
 
 	horizontal_adjustment.set_upper (new_end / frames_per_unit);
 	horizontal_adjustment.set_page_size (current_page_frames()/frames_per_unit);
@@ -1004,27 +1003,19 @@ Editor::handle_new_duration ()
 }
 
 void
-Editor::update_title_s (const string & snap_name)
-{
-	ENSURE_GUI_THREAD (*this, &Editor::update_title_s, snap_name)
-
-	update_title ();
-}
-
-void
 Editor::update_title ()
 {
 	ENSURE_GUI_THREAD (*this, &Editor::update_title)
 
-	if (session) {
-		bool dirty = session->dirty();
+	if (_session) {
+		bool dirty = _session->dirty();
 
 		string session_name;
 
-		if (session->snap_name() != session->name()) {
-			session_name = session->snap_name();
+		if (_session->snap_name() != _session->name()) {
+			session_name = _session->snap_name();
 		} else {
-			session_name = session->name();
+			session_name = _session->name();
 		}
 
 		if (dirty) {
@@ -1038,9 +1029,36 @@ Editor::update_title ()
 }
 
 void
-Editor::connect_to_session (Session *t)
+Editor::set_session (Session *t)
 {
-	session = t;
+	SessionHandlePtr::set_session (t);
+
+	zoom_range_clock.set_session (_session);
+	_playlist_selector->set_session (_session);
+	nudge_clock.set_session (_session);
+	_summary->set_session (_session);
+	_group_tabs->set_session (_session);
+	_route_groups->set_session (_session);
+	_regions->set_session (_session);
+	_snapshots->set_session (_session);
+	_routes->set_session (_session);
+	_locations->set_session (_session);
+
+	if (rhythm_ferret) {
+		rhythm_ferret->set_session (_session);
+	}
+
+	if (analysis_window) {
+		analysis_window->set_session (_session);
+	}
+
+	if (sfbrowser) {
+		sfbrowser->set_session (_session);
+	}
+
+	if (!_session) {
+		return;
+	}
 
 	compute_fixed_ruler_scale ();
 
@@ -1053,79 +1071,65 @@ Editor::connect_to_session (Session *t)
 
 	/* catch up with the playhead */
 
-	session->request_locate (playhead_cursor->current_frame);
+	_session->request_locate (playhead_cursor->current_frame);
 
 	update_title ();
 
-	session->GoingAway.connect (sigc::mem_fun(*this, &Editor::session_going_away));
-	session->history().Changed.connect (sigc::mem_fun (*this, &Editor::history_changed));
+	_session_connections.add_connection (_session->history().Changed.connect (boost::bind (&Editor::history_changed, this)));
 
 	/* These signals can all be emitted by a non-GUI thread. Therefore the
 	   handlers for them must not attempt to directly interact with the GUI,
 	   but use Gtkmm2ext::UI::instance()->call_slot();
 	*/
 
-	session_connections.push_back (session->TransportStateChange.connect (sigc::mem_fun(*this, &Editor::map_transport_state)));
-	session_connections.push_back (session->PositionChanged.connect (sigc::mem_fun(*this, &Editor::map_position_change)));
-	session_connections.push_back (session->RouteAdded.connect (sigc::mem_fun(*this, &Editor::handle_new_route)));
-	session_connections.push_back (session->DurationChanged.connect (sigc::mem_fun(*this, &Editor::handle_new_duration)));
-	session_connections.push_back (session->DirtyChanged.connect (sigc::mem_fun(*this, &Editor::update_title)));
-	session_connections.push_back (session->StateSaved.connect (sigc::mem_fun(*this, &Editor::update_title_s)));
-	session_connections.push_back (session->AskAboutPlaylistDeletion.connect (sigc::mem_fun(*this, &Editor::playlist_deletion_dialog)));
-
-	session_connections.push_back (session->TimecodeOffsetChanged.connect (sigc::mem_fun(*this, &Editor::update_just_timecode)));
+	_session_connections.add_connection (_session->TransportStateChange.connect (boost::bind (&Editor::map_transport_state, this)));
+	_session_connections.add_connection (_session->PositionChanged.connect (boost::bind (&Editor::map_position_change, this, _1)));
+	_session_connections.add_connection (_session->RouteAdded.connect (boost::bind (&Editor::handle_new_route, this, _1)));
+	_session_connections.add_connection (_session->DurationChanged.connect (boost::bind (&Editor::handle_new_duration, this)));
+	_session_connections.add_connection (_session->DirtyChanged.connect (boost::bind (&Editor::update_title, this)));
+	_session_connections.add_connection (_session->StateSaved.connect (boost::bind (&Editor::update_title, this)));
+	_session_connections.add_connection (_session->AskAboutPlaylistDeletion.connect (boost::bind (&Editor::playlist_deletion_dialog, this, _1)));
+	_session_connections.add_connection (_session->TimecodeOffsetChanged.connect (boost::bind (&Editor::update_just_timecode, this)));
+	_session_connections.add_connection (_session->tempo_map().StateChanged.connect (boost::bind (&Editor::tempo_map_changed, this, _1)));
+	_session_connections.add_connection (_session->Located.connect (boost::bind (&Editor::located, this)));
+	_session_connections.add_connection (_session->config.ParameterChanged.connect (boost::bind (&Editor::parameter_changed, this, _1)));
 
-	session_connections.push_back (session->tempo_map().StateChanged.connect (sigc::mem_fun(*this, &Editor::tempo_map_changed)));
-
-	session_connections.push_back (session->Located.connect (sigc::mem_fun (*this, &Editor::located)));
-	session_connections.push_back (session->config.ParameterChanged.connect (sigc::mem_fun (*this, &Editor::parameter_changed)));
-
-	zoom_range_clock.set_session (session);
-	_playlist_selector->set_session (session);
-	nudge_clock.set_session (session);
 	if (Profile->get_sae()) {
 		BBT_Time bbt;
 		bbt.bars = 0;
 		bbt.beats = 0;
 		bbt.ticks = 120;
-		nframes_t pos = session->tempo_map().bbt_duration_at (0, bbt, 1);
+		nframes_t pos = _session->tempo_map().bbt_duration_at (0, bbt, 1);
 		nudge_clock.set_mode(AudioClock::BBT);
 		nudge_clock.set (pos, true, 0, AudioClock::BBT);
 
 	} else {
-		nudge_clock.set (session->frame_rate() * 5, true, 0, AudioClock::Timecode); // default of 5 seconds
+		nudge_clock.set (_session->frame_rate() * 5, true, 0, AudioClock::Timecode); // default of 5 seconds
 	}
 
 	playhead_cursor->canvas_item.show ();
 
-	if (rhythm_ferret) {
-		rhythm_ferret->set_session (session);
-	}
-
-	if (analysis_window != 0)
-		analysis_window->set_session (session);
-
-	Location* loc = session->locations()->auto_loop_location();
+	Location* loc = _session->locations()->auto_loop_location();
 	if (loc == 0) {
-		loc = new Location (0, session->current_end_frame(), _("Loop"),(Location::Flags) (Location::IsAutoLoop | Location::IsHidden));
+		loc = new Location (0, _session->current_end_frame(), _("Loop"),(Location::Flags) (Location::IsAutoLoop | Location::IsHidden));
 		if (loc->start() == loc->end()) {
 			loc->set_end (loc->start() + 1);
 		}
-		session->locations()->add (loc, false);
-		session->set_auto_loop_location (loc);
+		_session->locations()->add (loc, false);
+		_session->set_auto_loop_location (loc);
 	} else {
 		// force name
 		loc->set_name (_("Loop"));
 	}
 
-	loc = session->locations()->auto_punch_location();
+	loc = _session->locations()->auto_punch_location();
 	if (loc == 0) {
-		loc = new Location (0, session->current_end_frame(), _("Punch"), (Location::Flags) (Location::IsAutoPunch | Location::IsHidden));
+		loc = new Location (0, _session->current_end_frame(), _("Punch"), (Location::Flags) (Location::IsAutoPunch | Location::IsHidden));
 		if (loc->start() == loc->end()) {
 			loc->set_end (loc->start() + 1);
 		}
-		session->locations()->add (loc, false);
-		session->set_auto_punch_location (loc);
+		_session->locations()->add (loc, false);
+		_session->set_auto_punch_location (loc);
 	} else {
 		// force name
 		loc->set_name (_("Punch"));
@@ -1133,26 +1137,26 @@ Editor::connect_to_session (Session *t)
 
 	boost::function<void (string)> pc (boost::bind (&Editor::parameter_changed, this, _1));
 	Config->map_parameters (pc);
-	session->config.map_parameters (pc);
+	_session->config.map_parameters (pc);
 
-	session->StateSaved.connect (sigc::mem_fun(*this, &Editor::session_state_saved));
 
 	refresh_location_display ();
-	session->locations()->added.connect (sigc::mem_fun(*this, &Editor::add_new_location));
-	session->locations()->removed.connect (sigc::mem_fun(*this, &Editor::location_gone));
-	session->locations()->changed.connect (sigc::mem_fun(*this, &Editor::refresh_location_display));
-	session->locations()->StateChanged.connect (sigc::mem_fun(*this, &Editor::refresh_location_display_s));
-	session->locations()->end_location()->changed.connect (sigc::mem_fun(*this, &Editor::end_location_changed));
 
-	if (sfbrowser) {
-		sfbrowser->set_session (session);
-	}
+	/* static signal - no need to drop connection when session is deleted (XXX or we are?)*/
+
+	_session->StateSaved.connect (sigc::mem_fun(*this, &Editor::session_state_saved));
+
+	_session_connections.add_connection (_session->locations()->added.connect (sigc::mem_fun(*this, &Editor::add_new_location)));
+	_session_connections.add_connection (_session->locations()->removed.connect (sigc::mem_fun(*this, &Editor::location_gone)));
+	_session_connections.add_connection (_session->locations()->changed.connect (sigc::mem_fun(*this, &Editor::refresh_location_display)));
+	_session_connections.add_connection (_session->locations()->StateChanged.connect (sigc::mem_fun(*this, &Editor::refresh_location_display_s)));
+	_session_connections.add_connection (_session->locations()->end_location()->changed.connect (sigc::mem_fun(*this, &Editor::end_location_changed)));
 
 	handle_new_duration ();
 
 	restore_ruler_visibility ();
 	//tempo_map_changed (Change (0));
-	session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks);
+	_session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks);
 
 	for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 		(static_cast<TimeAxisView*>(*i))->set_samples_per_unit (frames_per_unit);
@@ -1173,15 +1177,7 @@ Editor::connect_to_session (Session *t)
 	}
 
 	/* register for undo history */
-	session->register_with_memento_command_factory(_id, this);
-
-	_summary->connect_to_session (session);
-	_group_tabs->connect_to_session (session);
-	_route_groups->connect_to_session (session);
-	_regions->connect_to_session (session);
-	_snapshots->connect_to_session (session);
-	_routes->connect_to_session (session);
-	_locations->connect_to_session (session);
+	_session->register_with_memento_command_factory(_id, this);
 
 	start_updating ();
 }
@@ -1561,8 +1557,8 @@ Editor::analyze_region_selection()
 	if (analysis_window == 0) {
 		analysis_window = new AnalysisWindow();
 
-		if (session != 0)
-			analysis_window->set_session(session);
+		if (_session != 0)
+			analysis_window->set_session(_session);
 
 		analysis_window->show_all();
 	}
@@ -1579,8 +1575,8 @@ Editor::analyze_range_selection()
 	if (analysis_window == 0) {
 		analysis_window = new AnalysisWindow();
 
-		if (session != 0)
-			analysis_window->set_session(session);
+		if (_session != 0)
+			analysis_window->set_session(_session);
 
 		analysis_window->show_all();
 	}
@@ -2268,7 +2264,7 @@ Editor::set_state (const XMLNode& node, int /*version*/)
 	set_default_size (g.base_width, g.base_height);
 	move (x, y);
 
-	if (session && (prop = node.property ("playhead"))) {
+	if (_session && (prop = node.property ("playhead"))) {
 		nframes64_t pos = atol (prop->value().c_str());
 		playhead_cursor->set_position (pos);
 	} else {
@@ -2515,7 +2511,7 @@ Editor::trackview_by_y_position (double y)
 void
 Editor::snap_to_with_modifier (nframes64_t& start, GdkEvent const * event, int32_t direction, bool for_mark)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -2533,7 +2529,7 @@ Editor::snap_to_with_modifier (nframes64_t& start, GdkEvent const * event, int32
 void
 Editor::snap_to (nframes64_t& start, int32_t direction, bool for_mark)
 {
-	if (!session || _snap_mode == SnapOff) {
+	if (!_session || _snap_mode == SnapOff) {
 		return;
 	}
 
@@ -2543,24 +2539,24 @@ Editor::snap_to (nframes64_t& start, int32_t direction, bool for_mark)
 void
 Editor::timecode_snap_to_internal (nframes64_t& start, int32_t direction, bool /*for_mark*/)
 {
-	const nframes64_t one_timecode_second = (nframes64_t)(rint(session->timecode_frames_per_second()) * session->frames_per_timecode_frame());
-	nframes64_t one_timecode_minute = (nframes64_t)(rint(session->timecode_frames_per_second()) * session->frames_per_timecode_frame() * 60);
+	const nframes64_t one_timecode_second = (nframes64_t)(rint(_session->timecode_frames_per_second()) * _session->frames_per_timecode_frame());
+	nframes64_t one_timecode_minute = (nframes64_t)(rint(_session->timecode_frames_per_second()) * _session->frames_per_timecode_frame() * 60);
 
 	switch (_snap_type) {
 	case SnapToTimecodeFrame:
-		if (((direction == 0) && (fmod((double)start, (double)session->frames_per_timecode_frame()) > (session->frames_per_timecode_frame() / 2))) || (direction > 0)) {
-			start = (nframes64_t) (ceil ((double) start / session->frames_per_timecode_frame()) * session->frames_per_timecode_frame());
+		if (((direction == 0) && (fmod((double)start, (double)_session->frames_per_timecode_frame()) > (_session->frames_per_timecode_frame() / 2))) || (direction > 0)) {
+			start = (nframes64_t) (ceil ((double) start / _session->frames_per_timecode_frame()) * _session->frames_per_timecode_frame());
 		} else {
-			start = (nframes64_t) (floor ((double) start / session->frames_per_timecode_frame()) *  session->frames_per_timecode_frame());
+			start = (nframes64_t) (floor ((double) start / _session->frames_per_timecode_frame()) *  _session->frames_per_timecode_frame());
 		}
 		break;
 
 	case SnapToTimecodeSeconds:
-		if (session->timecode_offset_negative())
+		if (_session->timecode_offset_negative())
 		{
-			start += session->timecode_offset ();
+			start += _session->timecode_offset ();
 		} else {
-			start -= session->timecode_offset ();
+			start -= _session->timecode_offset ();
 		}
 		if (((direction == 0) && (start % one_timecode_second > one_timecode_second / 2)) || direction > 0) {
 			start = (nframes64_t) ceil ((double) start / one_timecode_second) * one_timecode_second;
@@ -2568,31 +2564,31 @@ Editor::timecode_snap_to_internal (nframes64_t& start, int32_t direction, bool /
 			start = (nframes64_t) floor ((double) start / one_timecode_second) * one_timecode_second;
 		}
 
-		if (session->timecode_offset_negative())
+		if (_session->timecode_offset_negative())
 		{
-			start -= session->timecode_offset ();
+			start -= _session->timecode_offset ();
 		} else {
-			start += session->timecode_offset ();
+			start += _session->timecode_offset ();
 		}
 		break;
 
 	case SnapToTimecodeMinutes:
-		if (session->timecode_offset_negative())
+		if (_session->timecode_offset_negative())
 		{
-			start += session->timecode_offset ();
+			start += _session->timecode_offset ();
 		} else {
-			start -= session->timecode_offset ();
+			start -= _session->timecode_offset ();
 		}
 		if (((direction == 0) && (start % one_timecode_minute > one_timecode_minute / 2)) || direction > 0) {
 			start = (nframes64_t) ceil ((double) start / one_timecode_minute) * one_timecode_minute;
 		} else {
 			start = (nframes64_t) floor ((double) start / one_timecode_minute) * one_timecode_minute;
 		}
-		if (session->timecode_offset_negative())
+		if (_session->timecode_offset_negative())
 		{
-			start -= session->timecode_offset ();
+			start -= _session->timecode_offset ();
 		} else {
-			start += session->timecode_offset ();
+			start += _session->timecode_offset ();
 		}
 		break;
 	default:
@@ -2604,8 +2600,8 @@ Editor::timecode_snap_to_internal (nframes64_t& start, int32_t direction, bool /
 void
 Editor::snap_to_internal (nframes64_t& start, int32_t direction, bool for_mark)
 {
-	const nframes64_t one_second = session->frame_rate();
-	const nframes64_t one_minute = session->frame_rate() * 60;
+	const nframes64_t one_second = _session->frame_rate();
+	const nframes64_t one_minute = _session->frame_rate() * 60;
 	nframes64_t presnap = start;
 	nframes64_t before;
 	nframes64_t after;
@@ -2641,31 +2637,31 @@ Editor::snap_to_internal (nframes64_t& start, int32_t direction, bool for_mark)
 		break;
 
 	case SnapToBar:
-		start = session->tempo_map().round_to_bar (start, direction);
+		start = _session->tempo_map().round_to_bar (start, direction);
 		break;
 
 	case SnapToBeat:
-		start = session->tempo_map().round_to_beat (start, direction);
+		start = _session->tempo_map().round_to_beat (start, direction);
 		break;
 
 	case SnapToAThirtysecondBeat:
-		start = session->tempo_map().round_to_beat_subdivision (start, 32, direction);
+		start = _session->tempo_map().round_to_beat_subdivision (start, 32, direction);
 		break;
 
 	case SnapToASixteenthBeat:
-		start = session->tempo_map().round_to_beat_subdivision (start, 16, direction);
+		start = _session->tempo_map().round_to_beat_subdivision (start, 16, direction);
 		break;
 
 	case SnapToAEighthBeat:
-		start = session->tempo_map().round_to_beat_subdivision (start, 8, direction);
+		start = _session->tempo_map().round_to_beat_subdivision (start, 8, direction);
 		break;
 
 	case SnapToAQuarterBeat:
-		start = session->tempo_map().round_to_beat_subdivision (start, 4, direction);
+		start = _session->tempo_map().round_to_beat_subdivision (start, 4, direction);
 		break;
 
 	case SnapToAThirdBeat:
-		start = session->tempo_map().round_to_beat_subdivision (start, 3, direction);
+		start = _session->tempo_map().round_to_beat_subdivision (start, 3, direction);
 		break;
 
 	case SnapToMark:
@@ -2673,7 +2669,7 @@ Editor::snap_to_internal (nframes64_t& start, int32_t direction, bool for_mark)
 			return;
 		}
 
-		session->locations()->marks_either_side (start, before, after);
+		_session->locations()->marks_either_side (start, before, after);
 
 		if (before == max_frames) {
 			start = after;
@@ -2971,8 +2967,8 @@ Editor::midi_panic ()
 {
 	cerr << "MIDI panic\n";
 
-	if (session) {
-		session->midi_panic();
+	if (_session) {
+		_session->midi_panic();
 	}
 }
 
@@ -3008,7 +3004,7 @@ Editor::convert_drop_to_paths (
 		guint                           /*info*/,
 		guint                           /*time*/)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return -1;
 	}
 
@@ -3120,7 +3116,7 @@ Editor::map_transport_state ()
 {
 	ENSURE_GUI_THREAD (*this, &Editor::map_transport_state)
 
-	if (session->transport_stopped()) {
+	if (_session->transport_stopped()) {
 		have_pending_keyboard_selection = false;
 	}
 
@@ -3162,17 +3158,17 @@ Editor::restore_state (State *state)
 void
 Editor::begin_reversible_command (string name)
 {
-	if (session) {
+	if (_session) {
 		before = &get_state();
-		session->begin_reversible_command (name);
+		_session->begin_reversible_command (name);
 	}
 }
 
 void
 Editor::commit_reversible_command ()
 {
-	if (session) {
-		session->commit_reversible_command (new MementoCommand<Editor>(*this, before, &get_state()));
+	if (_session) {
+		_session->commit_reversible_command (new MementoCommand<Editor>(*this, before, &get_state()));
 	}
 }
 
@@ -3205,20 +3201,20 @@ Editor::history_changed ()
 {
 	string label;
 
-	if (undo_action && session) {
-		if (session->undo_depth() == 0) {
+	if (undo_action && _session) {
+		if (_session->undo_depth() == 0) {
 			label = _("Undo");
 		} else {
-			label = string_compose(_("Undo (%1)"), session->next_undo());
+			label = string_compose(_("Undo (%1)"), _session->next_undo());
 		}
 		undo_action->property_label() = label;
 	}
 
-	if (redo_action && session) {
-		if (session->redo_depth() == 0) {
+	if (redo_action && _session) {
+		if (_session->redo_depth() == 0) {
 			label = _("Redo");
 		} else {
-			label = string_compose(_("Redo (%1)"), session->next_redo());
+			label = string_compose(_("Redo (%1)"), _session->next_redo());
 		}
 		redo_action->property_label() = label;
 	}
@@ -3394,7 +3390,7 @@ Editor::cycle_edit_mode ()
 void
 Editor::edit_mode_selection_done ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -3735,7 +3731,7 @@ Editor::edit_xfade (boost::weak_ptr<Crossfade> wxfade)
 		return;
 	}
 
-	CrossfadeEditor cew (*session, xfade, xfade->fade_in().get_min_y(), 1.0);
+	CrossfadeEditor cew (_session, xfade, xfade->fade_in().get_min_y(), 1.0);
 
 	ensure_float (cew);
 
@@ -3787,8 +3783,8 @@ Editor::get_grid_type_as_beats (bool& success, nframes64_t position)
 		break;
 
 	case SnapToBar:
-		if (session) {
-			return session->tempo_map().meter_at (position).beats_per_bar();
+		if (_session) {
+			return _session->tempo_map().meter_at (position).beats_per_bar();
 		}
 		break;
 
@@ -3899,8 +3895,8 @@ Editor::finish_cleanup ()
 Location*
 Editor::transport_loop_location()
 {
-	if (session) {
-		return session->locations()->auto_loop_location();
+	if (_session) {
+		return _session->locations()->auto_loop_location();
 	} else {
 		return 0;
 	}
@@ -3909,8 +3905,8 @@ Editor::transport_loop_location()
 Location*
 Editor::transport_punch_location()
 {
-	if (session) {
-		return session->locations()->auto_punch_location();
+	if (_session) {
+		return _session->locations()->auto_punch_location();
 	} else {
 		return 0;
 	}
@@ -4001,7 +3997,7 @@ Editor::new_playlists (TimeAxisView* v)
 {
 	begin_reversible_command (_("new playlists"));
 	vector<boost::shared_ptr<ARDOUR::Playlist> > playlists;
-	session->playlists->get (playlists);
+	_session->playlists->get (playlists);
 	mapover_tracks (sigc::bind (sigc::mem_fun (*this, &Editor::mapped_use_new_playlist), playlists), v, RouteGroup::Edit);
 	commit_reversible_command ();
 }
@@ -4017,7 +4013,7 @@ Editor::copy_playlists (TimeAxisView* v)
 {
 	begin_reversible_command (_("copy playlists"));
 	vector<boost::shared_ptr<ARDOUR::Playlist> > playlists;
-	session->playlists->get (playlists);
+	_session->playlists->get (playlists);
 	mapover_tracks (sigc::bind (sigc::mem_fun (*this, &Editor::mapped_use_copy_playlist), playlists), v, RouteGroup::Edit);
 	commit_reversible_command ();
 }
@@ -4032,7 +4028,7 @@ Editor::clear_playlists (TimeAxisView* v)
 {
 	begin_reversible_command (_("clear playlists"));
 	vector<boost::shared_ptr<ARDOUR::Playlist> > playlists;
-	session->playlists->get (playlists);
+	_session->playlists->get (playlists);
 	mapover_tracks (sigc::mem_fun (*this, &Editor::mapped_clear_playlist), v, RouteGroup::Edit);
 	commit_reversible_command ();
 }
@@ -4239,8 +4235,8 @@ Editor::post_zoom ()
 
 	ZoomChanged (); /* EMIT_SIGNAL */
 
-	if (session) {
-		cef = session->current_end_frame() + (current_page_frames() / 10);// Add a little extra so we can see the end marker
+	if (_session) {
+		cef = _session->current_end_frame() + (current_page_frames() / 10);// Add a little extra so we can see the end marker
 	}
 	horizontal_adjustment.set_upper (cef / frames_per_unit);
 
@@ -4265,7 +4261,7 @@ Editor::queue_visual_change (nframes64_t where)
 	   can reach.
 	*/
 
-	if (session && (where > session->current_end_frame())) {
+	if (_session && (where > _session->current_end_frame())) {
 		horizontal_adjustment.set_upper ((where + current_page_frames()) / frames_per_unit);
 	}
 
@@ -4332,9 +4328,9 @@ Editor::idle_visual_changer ()
 	nframes64_t csf=0, cef=0;
 	nframes64_t current_time_origin = (nframes64_t) floor (horizontal_adjustment.get_value() * frames_per_unit);
 
-	if (session) {
-		csf = session->current_start_frame();
-		cef = session->current_end_frame();
+	if (_session) {
+		csf = _session->current_start_frame();
+		cef = _session->current_end_frame();
 	}
 
 	/* if we seek beyond the current end of the canvas, move the end */
@@ -4397,7 +4393,7 @@ Editor::get_preferred_edit_position (bool ignore_playhead)
 
 	switch (ep) {
 	case EditAtPlayhead:
-		where = session->audible_frame();
+		where = _session->audible_frame();
 		break;
 
 	case EditAtSelectedMarker:
@@ -4431,7 +4427,7 @@ Editor::get_preferred_edit_position (bool ignore_playhead)
 void
 Editor::set_loop_range (nframes64_t start, nframes64_t end, string cmd)
 {
-	if (!session) return;
+	if (!_session) return;
 
 	begin_reversible_command (cmd);
 
@@ -4439,17 +4435,17 @@ Editor::set_loop_range (nframes64_t start, nframes64_t end, string cmd)
 
 	if ((tll = transport_loop_location()) == 0) {
 		Location* loc = new Location (start, end, _("Loop"),  Location::IsAutoLoop);
-		XMLNode &before = session->locations()->get_state();
-		session->locations()->add (loc, true);
-		session->set_auto_loop_location (loc);
-		XMLNode &after = session->locations()->get_state();
-		session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
+		XMLNode &before = _session->locations()->get_state();
+		_session->locations()->add (loc, true);
+		_session->set_auto_loop_location (loc);
+		XMLNode &after = _session->locations()->get_state();
+		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
 	} else {
 		XMLNode &before = tll->get_state();
 		tll->set_hidden (false, this);
 		tll->set (start, end);
 		XMLNode &after = tll->get_state();
-		session->add_command (new MementoCommand<Location>(*tll, &before, &after));
+		_session->add_command (new MementoCommand<Location>(*tll, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -4458,7 +4454,7 @@ Editor::set_loop_range (nframes64_t start, nframes64_t end, string cmd)
 void
 Editor::set_punch_range (nframes64_t start, nframes64_t end, string cmd)
 {
-	if (!session) return;
+	if (!_session) return;
 
 	begin_reversible_command (cmd);
 
@@ -4466,18 +4462,18 @@ Editor::set_punch_range (nframes64_t start, nframes64_t end, string cmd)
 
 	if ((tpl = transport_punch_location()) == 0) {
 		Location* loc = new Location (start, end, _("Loop"),  Location::IsAutoPunch);
-		XMLNode &before = session->locations()->get_state();
-		session->locations()->add (loc, true);
-		session->set_auto_loop_location (loc);
-		XMLNode &after = session->locations()->get_state();
-		session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
+		XMLNode &before = _session->locations()->get_state();
+		_session->locations()->add (loc, true);
+		_session->set_auto_loop_location (loc);
+		XMLNode &after = _session->locations()->get_state();
+		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
 	}
 	else {
 		XMLNode &before = tpl->get_state();
 		tpl->set_hidden (false, this);
 		tpl->set (start, end);
 		XMLNode &after = tpl->get_state();
-		session->add_command (new MementoCommand<Location>(*tpl, &before, &after));
+		_session->add_command (new MementoCommand<Location>(*tpl, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -4643,7 +4639,7 @@ Editor::show_rhythm_ferret ()
 		rhythm_ferret = new RhythmFerret(*this);
 	}
 
-	rhythm_ferret->set_session (session);
+	rhythm_ferret->set_session (_session);
 	rhythm_ferret->show ();
 	rhythm_ferret->present ();
 }
@@ -4652,7 +4648,7 @@ void
 Editor::show_global_port_matrix (ARDOUR::DataType t)
 {
 	if (_global_port_matrix[t] == 0) {
-		_global_port_matrix[t] = new GlobalPortMatrixWindow (session, t);
+		_global_port_matrix[t] = new GlobalPortMatrixWindow (_session, t);
 	}
 
 	_global_port_matrix[t]->show ();
@@ -4818,9 +4814,9 @@ Editor::handle_new_route (RouteList& routes)
 		DataType dt = route->input()->default_type();
 
 		if (dt == ARDOUR::DataType::AUDIO) {
-			rtv = new AudioTimeAxisView (*this, *session, route, *track_canvas);
+			rtv = new AudioTimeAxisView (*this, _session, route, *track_canvas);
 		} else if (dt == ARDOUR::DataType::MIDI) {
-			rtv = new MidiTimeAxisView (*this, *session, route, *track_canvas);
+			rtv = new MidiTimeAxisView (*this, _session, route, *track_canvas);
 		} else {
 			throw unknown_type();
 		}
@@ -4833,7 +4829,7 @@ Editor::handle_new_route (RouteList& routes)
 		rtv->view()->RegionViewAdded.connect (sigc::mem_fun (*this, &Editor::region_view_added));
 		rtv->view()->HeightChanged.connect (sigc::mem_fun (*this, &Editor::streamview_height_changed));
 
-		rtv->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &Editor::remove_route), rtv));
+		scoped_connect (rtv->GoingAway, boost::bind (&Editor::remove_route, this, rtv));
 	}
 
 	_routes->routes_added (new_views);
@@ -4954,18 +4950,18 @@ Editor::consider_auditioning (boost::shared_ptr<Region> region)
 	boost::shared_ptr<AudioRegion> r = boost::dynamic_pointer_cast<AudioRegion> (region);
 
 	if (r == 0) {
-		session->cancel_audition ();
+		_session->cancel_audition ();
 		return;
 	}
 
-	if (session->is_auditioning()) {
-		session->cancel_audition ();
+	if (_session->is_auditioning()) {
+		_session->cancel_audition ();
 		if (r == last_audition_region) {
 			return;
 		}
 	}
 
-	session->audition_region (r);
+	_session->audition_region (r);
 	last_audition_region = r;
 }
 
@@ -4979,7 +4975,7 @@ Editor::hide_a_region (boost::shared_ptr<Region> r)
 void
 Editor::remove_a_region (boost::shared_ptr<Region> r)
 {
-	session->remove_region_from_region_list (r);
+	_session->remove_region_from_region_list (r);
 }
 
 void
diff --git a/gtk2_ardour/editor.h b/gtk2_ardour/editor.h
index 36895bf784..a29df6ebb6 100644
--- a/gtk2_ardour/editor.h
+++ b/gtk2_ardour/editor.h
@@ -46,6 +46,8 @@
 #include <gtkmm2ext/dndtreeview.h>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
+
 #include "ardour/import_status.h"
 #include "ardour/tempo.h"
 #include "ardour/location.h"
@@ -155,14 +157,15 @@ struct EditorCursor {
 	sigc::signal<void, nframes64_t> PositionChanged;
 };
 
-class Editor : public PublicEditor
+class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARDOUR::SessionHandlePtr
 {
   public:
 	Editor ();
 	~Editor ();
 
-	void             connect_to_session (ARDOUR::Session *);
-	ARDOUR::Session* current_session() const { return session; }
+	void             set_session (ARDOUR::Session *);
+	ARDOUR::Session* session() const { return _session; }
+
 	void             first_idle ();
 	virtual bool     have_idled () const { return _have_idled; }
 
@@ -443,7 +446,6 @@ class Editor : public PublicEditor
 
 	void color_handler ();
 
-	ARDOUR::Session     *session; ///< The session that we are editing, or 0
 	bool                 constructed;
 
 	// to keep track of the playhead position for control_scroll
@@ -1893,7 +1895,7 @@ public:
 
 	int playlist_deletion_dialog (boost::shared_ptr<ARDOUR::Playlist>);
 
-	std::vector<sigc::connection> session_connections;
+	PBD::ScopedConnectionList session_connections;
 
 	/* tracking step changes of track height */
 
diff --git a/gtk2_ardour/editor_actions.cc b/gtk2_ardour/editor_actions.cc
index bc7d5ee7af..ac98482f4e 100644
--- a/gtk2_ardour/editor_actions.cc
+++ b/gtk2_ardour/editor_actions.cc
@@ -956,7 +956,7 @@ Editor::set_summary ()
 	Glib::RefPtr<Action> act = ActionManager::get_action (X_("Editor"), X_("ToggleSummary"));
 	if (act) {
 		Glib::RefPtr<ToggleAction> tact = Glib::RefPtr<ToggleAction>::cast_dynamic (act);
-		session->config.set_show_summary (tact->get_active ());
+		_session->config.set_show_summary (tact->get_active ());
 	}
 }
 
@@ -966,7 +966,7 @@ Editor::set_group_tabs ()
 	Glib::RefPtr<Action> act = ActionManager::get_action (X_("Editor"), X_("ToggleGroupTabs"));
 	if (act) {
 		Glib::RefPtr<ToggleAction> tact = Glib::RefPtr<ToggleAction>::cast_dynamic (act);
-		session->config.set_show_group_tabs (tact->get_active ());
+		_session->config.set_show_group_tabs (tact->get_active ());
 	}
 }
 
@@ -1350,7 +1350,7 @@ Editor::parameter_changed (std::string p)
 		toggle_meter_updating();
 	} else if (p == "show-summary") {
 
-		bool const s = session->config.get_show_summary ();
+		bool const s = _session->config.get_show_summary ();
  		if (s) {
  			_summary->show ();
  		} else {
@@ -1366,7 +1366,7 @@ Editor::parameter_changed (std::string p)
 		}
 	} else if (p == "show-group-tabs") {
 
-		bool const s = session->config.get_show_group_tabs ();
+		bool const s = _session->config.get_show_group_tabs ();
 		if (s) {
 			_group_tabs->show ();
 		} else {
diff --git a/gtk2_ardour/editor_audio_import.cc b/gtk2_ardour/editor_audio_import.cc
index 6ae445d828..108dcde7d3 100644
--- a/gtk2_ardour/editor_audio_import.cc
+++ b/gtk2_ardour/editor_audio_import.cc
@@ -73,14 +73,14 @@ using Glib::ustring;
 void
 Editor::add_external_audio_action (ImportMode mode_hint)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		MessageDialog msg (_("You can't import or embed an audiofile until you have a session loaded."));
 		msg.run ();
 		return;
 	}
-
+	
 	if (sfbrowser == 0) {
-		sfbrowser = new SoundFileOmega (*this, _("Add Existing Media"), session, 0, true, mode_hint);
+		sfbrowser = new SoundFileOmega (*this, _("Add Existing Media"), _session, 0, true, mode_hint);
 	} else {
 		sfbrowser->set_mode (mode_hint);
 	}
@@ -94,7 +94,7 @@ Editor::external_audio_dialog ()
 	vector<Glib::ustring> paths;
 	uint32_t track_cnt;
 
-	if (session == 0) {
+	if (_session == 0) {
 		MessageDialog msg (_("You can't import or embed an audiofile until you have a session loaded."));
 		msg.run ();
 		return;
@@ -113,7 +113,7 @@ Editor::external_audio_dialog ()
 	}
 
 	if (sfbrowser == 0) {
-		sfbrowser = new SoundFileOmega (*this, _("Add Existing Media"), session, track_cnt, true);
+		sfbrowser = new SoundFileOmega (*this, _("Add Existing Media"), _session, track_cnt, true);
 	} else {
 		sfbrowser->reset (track_cnt);
 	}
@@ -163,7 +163,7 @@ Editor::external_audio_dialog ()
 				where = playhead_cursor->current_frame;
 				break;
 			case ImportAtStart:
-				where = session->current_start_frame();
+				where = _session->current_start_frame();
 				break;
 		}
 
@@ -187,7 +187,7 @@ Editor::external_audio_dialog ()
 void
 Editor::session_import_dialog ()
 {
-	SessionImportDialog dialog (*session);
+	SessionImportDialog dialog (_session);
 	ensure_float (dialog);
 	dialog.run ();
 }
@@ -211,7 +211,7 @@ Editor::check_whether_and_how_to_import(string path, bool all_or_nothing)
 {
 	string wave_name (Glib::path_get_basename(path));
 
-	SourceMap all_sources = session->get_sources();
+	SourceMap all_sources = _session->get_sources();
 	bool wave_name_exists = false;
 
 	for (SourceMap::iterator i = all_sources.begin(); i != all_sources.end(); ++i) {
@@ -450,7 +450,7 @@ Editor::do_embed (vector<ustring> paths, ImportDisposition chns, ImportMode mode
 
   out:
 	if (ok) {
-		session->save_state ("");
+		_session->save_state ("");
 	}
 }
 
@@ -509,7 +509,7 @@ Editor::import_sndfiles (vector<ustring> paths, ImportMode mode, SrcQuality qual
 				 import_status.target_regions,
 				 import_status.target_tracks,
 				 import_status.track, false) == 0) {
-			session->save_state ("");
+			_session->save_state ("");
 		}
 
 		/* update position from results */
@@ -545,7 +545,7 @@ Editor::embed_sndfiles (vector<Glib::ustring> paths, bool multifile,
 
 			/* lets see if we can link it into the session */
 			
-			sys::path tmp = session->session_directory().sound_path() / Glib::path_get_basename(path);
+			sys::path tmp = _session->session_directory().sound_path() / Glib::path_get_basename(path);
 			linked_path = tmp.to_string();
 			
 			path_to_use = linked_path;
@@ -587,7 +587,7 @@ Editor::embed_sndfiles (vector<Glib::ustring> paths, bool multifile,
 			goto out;
 		}
 
-		if (check_sample_rate  && (finfo.samplerate != (int) session->frame_rate())) {
+		if (check_sample_rate  && (finfo.samplerate != (int) _session->frame_rate())) {
 			vector<string> choices;
 
 			if (multifile) {
@@ -650,10 +650,10 @@ Editor::embed_sndfiles (vector<Glib::ustring> paths, bool multifile,
 
 				boost::shared_ptr<Source> s;
 
-				if ((s = session->source_by_path_and_channel (path, n)) == 0) {
+				if ((s = _session->source_by_path_and_channel (path, n)) == 0) {
 
 					source = boost::dynamic_pointer_cast<AudioFileSource> (
-						SourceFactory::createReadable (DataType::AUDIO, *session,
+						SourceFactory::createReadable (DataType::AUDIO, *_session,
 									       path_to_use, n,
 									       (mode == ImportAsTapeTrack
 										? Source::Destructive
@@ -763,7 +763,7 @@ Editor::add_sources (vector<Glib::ustring> paths, SourceList& sources, nframes64
 	}
 
 	if (Config->get_output_auto_connect() & AutoConnectMaster) {
-		output_chan = (session->master_out() ? session->master_out()->n_inputs().n_audio() : input_chan);
+		output_chan = (_session->master_out() ? _session->master_out()->n_inputs().n_audio() : input_chan);
 	} else {
 		output_chan = input_chan;
 	}
@@ -822,7 +822,7 @@ Editor::finish_bringing_in_material (boost::shared_ptr<Region> region, uint32_t
 		begin_reversible_command (_("insert file"));
 		XMLNode &before = playlist->get_state();
 		playlist->add_region (copy, pos);
-		session->add_command (new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+		_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 		commit_reversible_command ();
 		break;
 	}
@@ -831,7 +831,7 @@ Editor::finish_bringing_in_material (boost::shared_ptr<Region> region, uint32_t
 	{
 		if (!existing_track) {
 			if (ar) {
-				list<boost::shared_ptr<AudioTrack> > at (session->new_audio_track (in_chans, out_chans, Normal, 0, 1));
+				list<boost::shared_ptr<AudioTrack> > at (_session->new_audio_track (in_chans, out_chans, Normal, 0, 1));
 
 				if (at.empty()) {
 					return -1;
@@ -839,7 +839,7 @@ Editor::finish_bringing_in_material (boost::shared_ptr<Region> region, uint32_t
 
 				existing_track = at.front();
 			} else if (mr) {
-				list<boost::shared_ptr<MidiTrack> > mt (session->new_midi_track (Normal, 0, 1));
+				list<boost::shared_ptr<MidiTrack> > mt (_session->new_midi_track (Normal, 0, 1));
 
 				if (mt.empty()) {
 					return -1;
@@ -862,7 +862,7 @@ Editor::finish_bringing_in_material (boost::shared_ptr<Region> region, uint32_t
 		if (!ar)
 			return -1;
 
-		list<boost::shared_ptr<AudioTrack> > at (session->new_audio_track (in_chans, out_chans, Destructive));
+		list<boost::shared_ptr<AudioTrack> > at (_session->new_audio_track (in_chans, out_chans, Destructive));
 		if (!at.empty()) {
 			boost::shared_ptr<Region> copy (RegionFactory::create (region));
 			at.front()->set_name (basename_nosuffix (copy->name()));
@@ -887,7 +887,7 @@ Editor::_import_thread (void *arg)
 void *
 Editor::import_thread ()
 {
-	session->import_audiofiles (import_status);
+	_session->import_audiofiles (import_status);
 	pthread_exit_pbd (0);
 	/*NOTREACHED*/
 	return 0;
diff --git a/gtk2_ardour/editor_audiotrack.cc b/gtk2_ardour/editor_audiotrack.cc
index 9baa689e51..ea703c415c 100644
--- a/gtk2_ardour/editor_audiotrack.cc
+++ b/gtk2_ardour/editor_audiotrack.cc
@@ -55,7 +55,7 @@ Editor::start_updating ()
 	RouteTimeAxisView* rtv;
 
 	//cerr << "Editor::start_updating () called" << endl;//DEBUG
-	if (is_mapped() && session) {
+	if (is_mapped() && _session) {
 		for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 			if ((rtv = dynamic_cast<RouteTimeAxisView*>(*i)) != 0) {
 				rtv->reset_meter ();
@@ -78,7 +78,7 @@ Editor::stop_updating ()
 	meters_running = false;
 	fast_screen_update_connection.disconnect();
 	//cerr << "Editor::stop_updating () called" << endl;//DEBUG
-	if (is_mapped() && session) {
+	if (is_mapped() && _session) {
 		for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 			if ((rtv = dynamic_cast<RouteTimeAxisView*>(*i)) != 0) {
 				rtv->hide_meter ();
@@ -105,7 +105,7 @@ Editor::fast_update_strips ()
 {
 	RouteTimeAxisView* rtv;
 
-	if (is_mapped() && session) {
+	if (is_mapped() && _session) {
 		for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 			if ((rtv = dynamic_cast<RouteTimeAxisView*>(*i)) != 0) {
 				rtv->fast_update ();
diff --git a/gtk2_ardour/editor_canvas.cc b/gtk2_ardour/editor_canvas.cc
index 97df092faa..f5eb29195f 100644
--- a/gtk2_ardour/editor_canvas.cc
+++ b/gtk2_ardour/editor_canvas.cc
@@ -329,7 +329,7 @@ Editor::track_canvas_size_allocated ()
 	_canvas_width = canvas_allocation.get_width();
 	_canvas_height = canvas_allocation.get_height();
 
-	if (session) {
+	if (_session) {
 		TrackViewList::iterator i;
 		double height = 0;
 
@@ -725,7 +725,7 @@ Editor::autoscroll_canvas ()
 void
 Editor::start_canvas_autoscroll (int dx, int dy)
 {
-	if (!session || autoscroll_active) {
+	if (!_session || autoscroll_active) {
 		return;
 	}
 
@@ -896,8 +896,8 @@ Editor::color_handler()
 /*
 	redisplay_tempo (true);
 
-	if (session)
-		session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks); // redraw metric markers
+	if (_session)
+	      _session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks); // redraw metric markers
 */
 }
 
diff --git a/gtk2_ardour/editor_component.cc b/gtk2_ardour/editor_component.cc
index 149ce6717c..e016f5bb50 100644
--- a/gtk2_ardour/editor_component.cc
+++ b/gtk2_ardour/editor_component.cc
@@ -17,33 +17,10 @@
 
 */
 
-#include "ardour/session.h"
 #include "editor_component.h"
 
-using namespace std;
-using namespace ARDOUR;
-
 EditorComponent::EditorComponent (Editor* e)
-	: _editor (e),
-	  _session (0)
+	: _editor (e)
 {
-
 }
 
-void
-EditorComponent::connect_to_session (Session* s)
-{
-	_session = s;
-
-	_session_connections.push_back (_session->GoingAway.connect (sigc::mem_fun (*this, &EditorComponent::session_going_away)));
-}
-
-void
-EditorComponent::session_going_away ()
-{
-	for (list<sigc::connection>::iterator i = _session_connections.begin(); i != _session_connections.end(); ++i) {
-		i->disconnect ();
-	}
-
-	_session = 0;
-}
diff --git a/gtk2_ardour/editor_component.h b/gtk2_ardour/editor_component.h
index 5c1ae8be2a..5b4f7e15d8 100644
--- a/gtk2_ardour/editor_component.h
+++ b/gtk2_ardour/editor_component.h
@@ -21,32 +21,19 @@
 #define __ardour_gtk_editor_component_h__
 
 #include <list>
-#include <sigc++/sigc++.h>
 
-namespace ARDOUR {
-	class Session;
-}
+#include "ardour/session_handle.h"
 
 class Editor;
 
-class EditorComponent
+class EditorComponent : public ARDOUR::SessionHandlePtr
 {
 public:
 	EditorComponent (Editor *);
 	virtual ~EditorComponent() {}
 
-	virtual void connect_to_session (ARDOUR::Session *);
-
 protected:
-
 	Editor* _editor;
-	ARDOUR::Session* _session;
-	std::list<sigc::connection> _session_connections;
-
-private:
-
-	void session_going_away ();
-
 };
 
 #endif
diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index 5ec2cb0439..bd97d42b4b 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -116,7 +116,7 @@ Drag::start_grab (GdkEvent* event, Gdk::Cursor *cursor)
 			      *cursor,
 			      event->button.time);
 
-	if (_editor->session && _editor->session->transport_rolling()) {
+	if (_editor->session() && _editor->session()->transport_rolling()) {
 		_was_rolling = true;
 	} else {
 		_was_rolling = false;
@@ -237,7 +237,7 @@ RegionDrag::RegionDrag (Editor* e, ArdourCanvas::Item* i, RegionView* p, list<Re
 	  _primary (p),
 	  _views (v)
 {
-	RegionView::RegionViewGoingAway.connect (sigc::mem_fun (*this, &RegionDrag::region_going_away));
+	death_connection = RegionView::RegionViewGoingAway.connect (sigc::mem_fun (*this, &RegionDrag::region_going_away));
 }
 
 void
@@ -828,7 +828,7 @@ RegionMoveDrag::finished (GdkEvent* /*event*/, bool movement_occurred)
 			insert_result = modified_playlists.insert (to_playlist);
 
 			if (insert_result.second) {
-				_editor->session->add_command (new MementoCommand<Playlist>(*to_playlist, &to_playlist->get_state(), 0));
+				_editor->session()->add_command (new MementoCommand<Playlist>(*to_playlist, &to_playlist->get_state(), 0));
 			}
 
 			to_playlist->add_region (new_region, where);
@@ -868,7 +868,7 @@ RegionMoveDrag::finished (GdkEvent* /*event*/, bool movement_occurred)
 			insert_result = modified_playlists.insert (playlist);
 
 			if (insert_result.second) {
-				_editor->session->add_command (new MementoCommand<Playlist>(*playlist, &playlist->get_state(), 0));
+				_editor->session()->add_command (new MementoCommand<Playlist>(*playlist, &playlist->get_state(), 0));
 			}
 			/* freeze to avoid lots of relayering in the case of a multi-region drag */
 			frozen_insert_result = frozen_playlists.insert(playlist);
@@ -910,7 +910,7 @@ RegionMoveDrag::finished (GdkEvent* /*event*/, bool movement_occurred)
 			insert_result = modified_playlists.insert (from_playlist);
 
 			if (insert_result.second) {
-				_editor->session->add_command (new MementoCommand<Playlist>(*from_playlist, &from_playlist->get_state(), 0));
+				_editor->session()->add_command (new MementoCommand<Playlist>(*from_playlist, &from_playlist->get_state(), 0));
 			}
 
 			from_playlist->remove_region (rv->region());
@@ -960,7 +960,7 @@ RegionMoveDrag::finished (GdkEvent* /*event*/, bool movement_occurred)
 
   out:
 	for (set<boost::shared_ptr<Playlist> >::iterator p = modified_playlists.begin(); p != modified_playlists.end(); ++p) {
-		_editor->session->add_command (new MementoCommand<Playlist>(*(*p), 0, &(*p)->get_state()));
+		_editor->session()->add_command (new MementoCommand<Playlist>(*(*p), 0, &(*p)->get_state()));
 	}
 
 	_editor->commit_reversible_command ();
@@ -1245,7 +1245,7 @@ RegionInsertDrag::finished (GdkEvent* /*event*/, bool /*movement_occurred*/)
 	_editor->begin_reversible_command (_("insert region"));
 	XMLNode& before = playlist->get_state ();
 	playlist->add_region (_primary->region (), _last_frame_position);
-	_editor->session->add_command (new MementoCommand<Playlist> (*playlist, &before, &playlist->get_state()));
+	_editor->session()->add_command (new MementoCommand<Playlist> (*playlist, &before, &playlist->get_state()));
 	_editor->commit_reversible_command ();
 
 	delete _primary;
@@ -1570,7 +1570,7 @@ TrimDrag::motion (GdkEvent* event, bool first_move)
 			insert_result = _editor->motion_frozen_playlists.insert (pl);
 
 			if (insert_result.second) {
-				_editor->session->add_command(new MementoCommand<Playlist>(*pl, &pl->get_state(), 0));
+				_editor->session()->add_command(new MementoCommand<Playlist>(*pl, &pl->get_state(), 0));
 				pl->freeze();
 			}
 		}
@@ -1668,7 +1668,7 @@ TrimDrag::finished (GdkEvent* event, bool movement_occurred)
 		for (set<boost::shared_ptr<Playlist> >::iterator p = _editor->motion_frozen_playlists.begin(); p != _editor->motion_frozen_playlists.end(); ++p) {
 			(*p)->thaw ();
 			if (_have_transaction) {
-				_editor->session->add_command (new MementoCommand<Playlist>(*(*p).get(), 0, &(*p)->get_state()));
+				_editor->session()->add_command (new MementoCommand<Playlist>(*(*p).get(), 0, &(*p)->get_state()));
 			}
 		}
 
@@ -1750,7 +1750,7 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 
 	BBT_Time when;
 
-	TempoMap& map (_editor->session->tempo_map());
+	TempoMap& map (_editor->session()->tempo_map());
 	map.bbt_time (_last_pointer_frame, when);
 
 	if (_copy == true) {
@@ -1758,7 +1758,7 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		XMLNode &before = map.get_state();
 		map.add_meter (_marker->meter(), when);
 		XMLNode &after = map.get_state();
-		_editor->session->add_command(new MementoCommand<TempoMap>(map, &before, &after));
+		_editor->session()->add_command(new MementoCommand<TempoMap>(map, &before, &after));
 		_editor->commit_reversible_command ();
 
 		// delete the dummy marker we used for visual representation of copying.
@@ -1769,7 +1769,7 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		XMLNode &before = map.get_state();
 		map.move_meter (_marker->meter(), when);
 		XMLNode &after = map.get_state();
-		_editor->session->add_command(new MementoCommand<TempoMap>(map, &before, &after));
+		_editor->session()->add_command(new MementoCommand<TempoMap>(map, &before, &after));
 		_editor->commit_reversible_command ();
 	}
 }
@@ -1842,7 +1842,7 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 
 	BBT_Time when;
 
-	TempoMap& map (_editor->session->tempo_map());
+	TempoMap& map (_editor->session()->tempo_map());
 	map.bbt_time (_last_pointer_frame, when);
 
 	if (_copy == true) {
@@ -1850,7 +1850,7 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		XMLNode &before = map.get_state();
 		map.add_tempo (_marker->tempo(), when);
 		XMLNode &after = map.get_state();
-		_editor->session->add_command (new MementoCommand<TempoMap>(map, &before, &after));
+		_editor->session()->add_command (new MementoCommand<TempoMap>(map, &before, &after));
 		_editor->commit_reversible_command ();
 
 		// delete the dummy marker we used for visual representation of copying.
@@ -1861,7 +1861,7 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		XMLNode &before = map.get_state();
 		map.move_tempo (_marker->tempo(), when);
 		XMLNode &after = map.get_state();
-		_editor->session->add_command (new MementoCommand<TempoMap>(map, &before, &after));
+		_editor->session()->add_command (new MementoCommand<TempoMap>(map, &before, &after));
 		_editor->commit_reversible_command ();
 	}
 }
@@ -1892,12 +1892,12 @@ CursorDrag::start_grab (GdkEvent* event, Gdk::Cursor* c)
 	if (_cursor == _editor->playhead_cursor) {
 		_editor->_dragging_playhead = true;
 
-		if (_editor->session && _was_rolling && _stop) {
-			_editor->session->request_stop ();
+		if (_editor->session() && _was_rolling && _stop) {
+			_editor->session()->request_stop ();
 		}
 
-		if (_editor->session && _editor->session->is_auditioning()) {
-			_editor->session->cancel_audition ();
+		if (_editor->session() && _editor->session()->is_auditioning()) {
+			_editor->session()->cancel_audition ();
 		}
 	}
 
@@ -1937,8 +1937,8 @@ CursorDrag::finished (GdkEvent* event, bool movement_occurred)
 	motion (event, false);
 
 	if (_item == &_editor->playhead_cursor->canvas_item) {
-		if (_editor->session) {
-			_editor->session->request_locate (_editor->playhead_cursor->current_frame, _was_rolling);
+		if (_editor->session()) {
+			_editor->session()->request_locate (_editor->playhead_cursor->current_frame, _was_rolling);
 			_editor->_pending_locate_request = true;
 		}
 	}
@@ -2031,7 +2031,7 @@ FadeInDrag::finished (GdkEvent* event, bool movement_occurred)
 		tmp->audio_region()->set_fade_in_active (true);
 
 		XMLNode &after = alist->get_state();
-		_editor->session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
+		_editor->session()->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
 	}
 
 	_editor->commit_reversible_command ();
@@ -2128,7 +2128,7 @@ FadeOutDrag::finished (GdkEvent* event, bool movement_occurred)
 		tmp->audio_region()->set_fade_out_active (true);
 
 		XMLNode &after = alist->get_state();
-		_editor->session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
+		_editor->session()->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
 	}
 
 	_editor->commit_reversible_command ();
@@ -2205,7 +2205,7 @@ MarkerDrag::start_grab (GdkEvent* event, Gdk::Cursor* cursor)
 		if (e < max_frames) {
 			++e;
 		}
-		_editor->session->locations()->find_all_between (s, e, ll, Location::Flags (0));
+		_editor->session()->locations()->find_all_between (s, e, ll, Location::Flags (0));
 		for (Locations::LocationList::iterator i = ll.begin(); i != ll.end(); ++i) {
 			Editor::LocationMarkers* lm = _editor->find_location_markers (*i);
 			if (lm) {
@@ -2415,7 +2415,7 @@ MarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 	_editor->_dragging_edit_point = false;
 
 	_editor->begin_reversible_command ( _("move marker") );
-	XMLNode &before = _editor->session->locations()->get_state();
+	XMLNode &before = _editor->session()->locations()->get_state();
 
 	MarkerSelection::iterator i;
 	list<Location*>::iterator x;
@@ -2441,8 +2441,8 @@ MarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		}
 	}
 
-	XMLNode &after = _editor->session->locations()->get_state();
-	_editor->session->add_command(new MementoCommand<Locations>(*(_editor->session->locations()), &before, &after));
+	XMLNode &after = _editor->session()->locations()->get_state();
+	_editor->session()->add_command(new MementoCommand<Locations>(*(_editor->session()->locations()), &before, &after));
 	_editor->commit_reversible_command ();
 
 	_line->hide();
@@ -2855,9 +2855,9 @@ ScrubDrag::motion (GdkEvent* /*event*/, bool)
 void
 ScrubDrag::finished (GdkEvent* /*event*/, bool movement_occurred)
 {
-	if (movement_occurred && _editor->session) {
+	if (movement_occurred && _editor->session()) {
 		/* make sure we stop */
-		_editor->session->request_transport_speed (0.0);
+		_editor->session()->request_transport_speed (0.0);
 	}
 }
 
@@ -2875,7 +2875,7 @@ SelectionDrag::start_grab (GdkEvent* event, Gdk::Cursor*)
 	nframes64_t start = 0;
 	nframes64_t end = 0;
 
-	if (_editor->session == 0) {
+	if (_editor->session() == 0) {
 		return;
 	}
 
@@ -3059,7 +3059,7 @@ SelectionDrag::motion (GdkEvent* event, bool first_move)
 void
 SelectionDrag::finished (GdkEvent* event, bool movement_occurred)
 {
-	Session* s = _editor->session;
+	Session* s = _editor->session();
 
 	if (movement_occurred) {
 		motion (event, false);
@@ -3113,7 +3113,7 @@ RangeMarkerBarDrag::RangeMarkerBarDrag (Editor* e, ArdourCanvas::Item* i, Operat
 void
 RangeMarkerBarDrag::start_grab (GdkEvent* event, Gdk::Cursor *)
 {
-	if (_editor->session == 0) {
+	if (_editor->session() == 0) {
 		return;
 	}
 
@@ -3246,8 +3246,8 @@ RangeMarkerBarDrag::finished (GdkEvent* event, bool movement_occurred)
 		case CreateCDMarker:
 		    {
 			_editor->begin_reversible_command (_("new range marker"));
-			XMLNode &before = _editor->session->locations()->get_state();
-			_editor->session->locations()->next_available_name(rangename,"unnamed");
+			XMLNode &before = _editor->session()->locations()->get_state();
+			_editor->session()->locations()->next_available_name(rangename,"unnamed");
 			if (_operation == CreateCDMarker) {
 				flags = Location::IsRangeMarker | Location::IsCDMarker;
 				_editor->cd_marker_bar_drag_rect->hide();
@@ -3257,9 +3257,9 @@ RangeMarkerBarDrag::finished (GdkEvent* event, bool movement_occurred)
 				_editor->range_bar_drag_rect->hide();
 			}
 			newloc = new Location(_editor->temp_location->start(), _editor->temp_location->end(), rangename, (Location::Flags) flags);
-			_editor->session->locations()->add (newloc, true);
-			XMLNode &after = _editor->session->locations()->get_state();
-			_editor->session->add_command(new MementoCommand<Locations>(*(_editor->session->locations()), &before, &after));
+			_editor->session()->locations()->add (newloc, true);
+			XMLNode &after = _editor->session()->locations()->get_state();
+			_editor->session()->add_command(new MementoCommand<Locations>(*(_editor->session()->locations()), &before, &after));
 			_editor->commit_reversible_command ();
 			break;
 		    }
@@ -3277,14 +3277,14 @@ RangeMarkerBarDrag::finished (GdkEvent* event, bool movement_occurred)
 			nframes64_t start;
 			nframes64_t end;
 
-			_editor->session->locations()->marks_either_side (_grab_frame, start, end);
+			_editor->session()->locations()->marks_either_side (_grab_frame, start, end);
 
 			if (end == max_frames) {
-				end = _editor->session->current_end_frame ();
+				end = _editor->session()->current_end_frame ();
 			}
 
 			if (start == max_frames) {
-				start = _editor->session->current_start_frame ();
+				start = _editor->session()->current_start_frame ();
 			}
 
 			switch (_editor->mouse_mode) {
diff --git a/gtk2_ardour/editor_drag.h b/gtk2_ardour/editor_drag.h
index d2593b2463..170c9a8080 100644
--- a/gtk2_ardour/editor_drag.h
+++ b/gtk2_ardour/editor_drag.h
@@ -160,6 +160,7 @@ protected:
 
 private:
 	void region_going_away (RegionView *);
+	boost::signals2::scoped_connection death_connection;
 };
 
 
diff --git a/gtk2_ardour/editor_export_audio.cc b/gtk2_ardour/editor_export_audio.cc
index c8d27037a3..7d0fcc1bf9 100644
--- a/gtk2_ardour/editor_export_audio.cc
+++ b/gtk2_ardour/editor_export_audio.cc
@@ -59,7 +59,7 @@ void
 Editor::export_audio ()
 {
 	ExportDialog dialog (*this);
-	dialog.set_session (session);
+	dialog.set_session (_session);
 	dialog.run();
 }
 
@@ -67,7 +67,7 @@ void
 Editor::export_selection ()
 {
 	ExportSelectionDialog dialog (*this);
-	dialog.set_session (session);
+	dialog.set_session (_session);
 	dialog.run();
 }
 
@@ -86,7 +86,7 @@ Editor::export_range ()
 
 	if (((l = find_location_from_marker (marker, is_start)) != 0) && (l->end() > l->start())) {
 		ExportRangeDialog dialog (*this, l->id().to_s());
-		dialog.set_session (session);
+		dialog.set_session (_session);
 		dialog.run();
 	}
 }
@@ -107,7 +107,7 @@ Editor::export_region ()
 		AudioTrack & track (dynamic_cast<AudioTrack &> (*rtv.route()));
 
 		ExportRegionDialog dialog (*this, region, track);
-		dialog.set_session (session);
+		dialog.set_session (_session);
 		dialog.run();
 
 	} catch (std::bad_cast & e) {
@@ -173,7 +173,7 @@ Editor::write_region (string path, boost::shared_ptr<AudioRegion> region)
 	vector<boost::shared_ptr<AudioFileSource> > sources;
 	uint32_t nchans;
 
-	const string sound_directory = session->session_directory().sound_path().to_string();
+	const string sound_directory = _session->session_directory().sound_path().to_string();
 
 	nchans = region->n_channels();
 
@@ -214,9 +214,9 @@ Editor::write_region (string path, boost::shared_ptr<AudioRegion> region)
 
 			try {
 				fs = boost::dynamic_pointer_cast<AudioFileSource> (
-						SourceFactory::createWritable (DataType::AUDIO, *session,
+						SourceFactory::createWritable (DataType::AUDIO, *_session,
 								path, true,
-								false, session->frame_rate()));
+								false, _session->frame_rate()));
 			}
 
 			catch (failed_constructor& err) {
@@ -323,7 +323,7 @@ Editor::write_audio_range (AudioPlaylist& playlist, const ChanCount& count, list
 	string path;
 	vector<boost::shared_ptr<AudioFileSource> > sources;
 
-	const string sound_directory = session->session_directory().sound_path().to_string();
+	const string sound_directory = _session->session_directory().sound_path().to_string();
 
 	uint32_t channels = count.n_audio();
 
@@ -353,9 +353,9 @@ Editor::write_audio_range (AudioPlaylist& playlist, const ChanCount& count, list
 
 		try {
 			fs = boost::dynamic_pointer_cast<AudioFileSource> (
-					SourceFactory::createWritable (DataType::AUDIO, *session,
+					SourceFactory::createWritable (DataType::AUDIO, *_session,
 							path, true,
-							false, session->frame_rate()));
+							false, _session->frame_rate()));
 		}
 
 		catch (failed_constructor& err) {
diff --git a/gtk2_ardour/editor_imageframe.cc b/gtk2_ardour/editor_imageframe.cc
index 3e99f9e6bf..705c68586c 100644
--- a/gtk2_ardour/editor_imageframe.cc
+++ b/gtk2_ardour/editor_imageframe.cc
@@ -1092,14 +1092,14 @@ Editor::handle_new_imageframe_time_axis_view(const string & track_name, void* sr
 	row[route_display_columns.tv] = iftav;
 	route_list_display.get_selection()->select (row);
 
-	iftav->GoingAway.connect(sigc::bind(sigc::mem_fun(*this, &Editor::remove_route), (TimeAxisView*)iftav)) ;
+	scoped_connect (iftav->GoingAway, boost::bind (&Editor::remove_route, this, (TimeAxisView*)iftav));
 	iftav->gui_changed.connect(sigc::mem_fun(*this, &Editor::handle_gui_changes)) ;
 }
 
 void
 Editor::handle_new_imageframe_marker_time_axis_view(const string & track_name, TimeAxisView* marked_track)
 {
-	MarkerTimeAxis* mta = new MarkerTimeAxis (*this, *this->current_session(), *track_canvas, track_name, marked_track) ;
+	MarkerTimeAxis* mta = new MarkerTimeAxis (*this, *this->session(), *track_canvas, track_name, marked_track) ;
 	((ImageFrameTimeAxis*)marked_track)->add_marker_time_axis(mta, this) ;
 	track_views.push_back(mta) ;
 
@@ -1109,7 +1109,7 @@ Editor::handle_new_imageframe_marker_time_axis_view(const string & track_name, T
 	row[route_display_columns.tv] = mta;
 	route_list_display.get_selection()->select (row);
 
-	mta->GoingAway.connect(sigc::bind(sigc::mem_fun(*this, &Editor::remove_route), (TimeAxisView*)mta)) ;
+	scoped_connect (mta->GoingAway, boost::bind (&Editor::remove_route, this, (TimeAxisView*)mta));
  }
 
 
diff --git a/gtk2_ardour/editor_keyboard.cc b/gtk2_ardour/editor_keyboard.cc
index ba33e23fea..4b16a4b8a2 100644
--- a/gtk2_ardour/editor_keyboard.cc
+++ b/gtk2_ardour/editor_keyboard.cc
@@ -95,7 +95,7 @@ Editor::kbd_mute_unmute_region ()
 			(*i)->region()->set_muted (!(*i)->region()->muted ());
 			XMLNode &after = (*i)->region()->playlist()->get_state ();
 
-			session->add_command (new MementoCommand<ARDOUR::Playlist>(*((*i)->region()->playlist()), &before, &after));
+			_session->add_command (new MementoCommand<ARDOUR::Playlist>(*((*i)->region()->playlist()), &before, &after));
 
 		}
 
@@ -109,7 +109,7 @@ Editor::kbd_mute_unmute_region ()
 		entered_regionview->region()->set_muted (!entered_regionview->region()->muted());
 
 		XMLNode &after = entered_regionview->region()->playlist()->get_state();
-		session->add_command (new MementoCommand<ARDOUR::Playlist>(*(entered_regionview->region()->playlist()), &before, &after));
+		_session->add_command (new MementoCommand<ARDOUR::Playlist>(*(entered_regionview->region()->playlist()), &before, &after));
 		commit_reversible_command();
 
 	}
diff --git a/gtk2_ardour/editor_keys.cc b/gtk2_ardour/editor_keys.cc
index b9df06d358..0d46665782 100644
--- a/gtk2_ardour/editor_keys.cc
+++ b/gtk2_ardour/editor_keys.cc
@@ -41,13 +41,13 @@ using namespace PBD;
 void
 Editor::keyboard_selection_finish (bool add)
 {
-	if (session && have_pending_keyboard_selection) {
+	if (_session && have_pending_keyboard_selection) {
 
 		nframes64_t end;
 		bool ignored;
 
-		if (session->transport_rolling()) {
-			end = session->audible_frame();
+		if (_session->transport_rolling()) {
+			end = _session->audible_frame();
 		} else {
 			if (!mouse_frame (end, ignored)) {
 				return;
@@ -67,9 +67,9 @@ Editor::keyboard_selection_finish (bool add)
 void
 Editor::keyboard_selection_begin ()
 {
-	if (session) {
-		if (session->transport_rolling()) {
-			pending_keyboard_selection_start = session->audible_frame();
+	if (_session) {
+		if (_session->transport_rolling()) {
+			pending_keyboard_selection_start = _session->audible_frame();
 			have_pending_keyboard_selection = true;
 		} else {
 			bool ignored;
diff --git a/gtk2_ardour/editor_locations.cc b/gtk2_ardour/editor_locations.cc
index 7031be410e..d4117b86b0 100644
--- a/gtk2_ardour/editor_locations.cc
+++ b/gtk2_ardour/editor_locations.cc
@@ -32,9 +32,9 @@ EditorLocations::EditorLocations (Editor* e)
 }
 
 void
-EditorLocations::connect_to_session (ARDOUR::Session* s)
+EditorLocations::set_session (ARDOUR::Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 	locations->set_session (s);
 }
 
diff --git a/gtk2_ardour/editor_locations.h b/gtk2_ardour/editor_locations.h
index 3375b338bd..6d4d3128e4 100644
--- a/gtk2_ardour/editor_locations.h
+++ b/gtk2_ardour/editor_locations.h
@@ -33,7 +33,7 @@ class EditorLocations : public EditorComponent
   public:
 	EditorLocations (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	Gtk::Widget& widget ();
 
diff --git a/gtk2_ardour/editor_markers.cc b/gtk2_ardour/editor_markers.cc
index fa9fd83cc2..4d9828a14d 100644
--- a/gtk2_ardour/editor_markers.cc
+++ b/gtk2_ardour/editor_markers.cc
@@ -332,8 +332,8 @@ Editor::refresh_location_display ()
 {
 	ENSURE_GUI_THREAD (*this, &Editor::refresh_location_display)
 
-	if (session) {
-		session->locations()->apply (*this, &Editor::refresh_location_display_internal);
+	if (_session) {
+		_session->locations()->apply (*this, &Editor::refresh_location_display_internal);
 	}
 }
 
@@ -342,8 +342,8 @@ Editor::refresh_location_display_s (Change ignored)
 {
 	ENSURE_GUI_THREAD (*this, &Editor::refresh_location_display_s, ignored)
 
-	if (session) {
-		session->locations()->apply (*this, &Editor::refresh_location_display_internal);
+	if (_session) {
+		_session->locations()->apply (*this, &Editor::refresh_location_display_internal);
 	}
 }
 
@@ -396,18 +396,18 @@ Editor::mouse_add_new_marker (nframes64_t where, bool is_cd, bool is_xrun)
 		markerprefix = "mark";
 	}
 
-	if (session) {
-		session->locations()->next_available_name(markername, markerprefix);
+	if (_session) {
+		_session->locations()->next_available_name(markername, markerprefix);
 		if (!is_xrun && !choose_new_marker_name(markername)) {
 			return;
 		}
 		Location *location = new Location (where, where, markername, (Location::Flags) flags);
-		session->begin_reversible_command (_("add marker"));
-		XMLNode &before = session->locations()->get_state();
-		session->locations()->add (location, true);
-		XMLNode &after = session->locations()->get_state();
-		session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-		session->commit_reversible_command ();
+		_session->begin_reversible_command (_("add marker"));
+		XMLNode &before = _session->locations()->get_state();
+		_session->locations()->add (location, true);
+		XMLNode &after = _session->locations()->get_state();
+		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+		_session->commit_reversible_command ();
 
 		/* find the marker we just added */
 
@@ -436,7 +436,7 @@ Editor::remove_marker (ArdourCanvas::Item& item, GdkEvent*)
 
 	Location* loc = find_location_from_marker (marker, is_start);
 
-	if (session && loc) {
+	if (_session && loc) {
 	  	Glib::signal_idle().connect (sigc::bind (sigc::mem_fun(*this, &Editor::really_remove_marker), loc));
 	}
 }
@@ -444,12 +444,12 @@ Editor::remove_marker (ArdourCanvas::Item& item, GdkEvent*)
 gint
 Editor::really_remove_marker (Location* loc)
 {
-	session->begin_reversible_command (_("remove marker"));
-	XMLNode &before = session->locations()->get_state();
-	session->locations()->remove (loc);
-	XMLNode &after = session->locations()->get_state();
-	session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	_session->begin_reversible_command (_("remove marker"));
+	XMLNode &before = _session->locations()->get_state();
+	_session->locations()->remove (loc);
+	XMLNode &after = _session->locations()->get_state();
+	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 	return FALSE;
 }
 
@@ -765,15 +765,15 @@ Editor::marker_menu_play_from ()
 	if ((l = find_location_from_marker (marker, is_start)) != 0) {
 
 		if (l->is_mark()) {
-			session->request_locate (l->start(), true);
+			_session->request_locate (l->start(), true);
 		}
 		else {
-			//session->request_bounded_roll (l->start(), l->end());
+			//_session->request_bounded_roll (l->start(), l->end());
 
 			if (is_start) {
-				session->request_locate (l->start(), true);
+				_session->request_locate (l->start(), true);
 			} else {
-				session->request_locate (l->end(), true);
+				_session->request_locate (l->end(), true);
 			}
 		}
 	}
@@ -795,13 +795,13 @@ Editor::marker_menu_set_playhead ()
 	if ((l = find_location_from_marker (marker, is_start)) != 0) {
 
 		if (l->is_mark()) {
-			session->request_locate (l->start(), false);
+			_session->request_locate (l->start(), false);
 		}
 		else {
 			if (is_start) {
-				session->request_locate (l->start(), false);
+				_session->request_locate (l->start(), false);
 			} else {
-				session->request_locate (l->end(), false);
+				_session->request_locate (l->end(), false);
 			}
 		}
 	}
@@ -811,7 +811,7 @@ void
 Editor::marker_menu_range_to_next ()
 {
 	Marker* marker;
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -829,14 +829,14 @@ Editor::marker_menu_range_to_next ()
 
 	nframes64_t start;
 	nframes64_t end;
-	session->locations()->marks_either_side (marker->position(), start, end);
+	_session->locations()->marks_either_side (marker->position(), start, end);
 
 	if (end != max_frames) {
 		string range_name = l->name();
 		range_name += "-range";
 
 		Location* newrange = new Location (marker->position(), end, range_name, Location::IsRangeMarker);
-		session->locations()->add (newrange);
+		_session->locations()->add (newrange);
 	}
 }
 
@@ -856,13 +856,13 @@ Editor::marker_menu_set_from_playhead ()
 	if ((l = find_location_from_marker (marker, is_start)) != 0) {
 
 		if (l->is_mark()) {
-			l->set_start (session->audible_frame ());
+			l->set_start (_session->audible_frame ());
 		}
 		else {
 			if (is_start) {
-				l->set_start (session->audible_frame ());
+				l->set_start (_session->audible_frame ());
 			} else {
-				l->set_end (session->audible_frame ());
+				l->set_end (_session->audible_frame ());
 			}
 		}
 	}
@@ -923,10 +923,10 @@ Editor::marker_menu_play_range ()
 	if ((l = find_location_from_marker (marker, is_start)) != 0) {
 
 		if (l->is_mark()) {
-			session->request_locate (l->start(), true);
+			_session->request_locate (l->start(), true);
 		}
 		else {
-			session->request_bounded_roll (l->start(), l->end());
+			_session->request_bounded_roll (l->start(), l->end());
 
 		}
 	}
@@ -951,8 +951,8 @@ Editor::marker_menu_loop_range ()
 			l2->set (l->start(), l->end());
 
 			// enable looping, reposition and start rolling
-			session->request_play_loop(true);
-			session->request_locate (l2->start(), true);
+			_session->request_play_loop(true);
+			_session->request_locate (l2->start(), true);
 		}
 	}
 }
@@ -1072,13 +1072,13 @@ Editor::marker_menu_rename ()
 	}
 
 	begin_reversible_command ( _("rename marker") );
-	XMLNode &before = session->locations()->get_state();
+	XMLNode &before = _session->locations()->get_state();
 
 	dialog.get_result(txt);
 	loc->set_name (txt);
 
-	XMLNode &after = session->locations()->get_state();
-	session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
+	XMLNode &after = _session->locations()->get_state();
+	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
 	commit_reversible_command ();
 }
 
@@ -1106,13 +1106,13 @@ Editor::new_transport_marker_menu_set_punch ()
 void
 Editor::update_loop_range_view (bool visibility)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
 	Location* tll;
 
-	if (session->get_play_loop() && ((tll = transport_loop_location()) != 0)) {
+	if (_session->get_play_loop() && ((tll = transport_loop_location()) != 0)) {
 
 		double x1 = frame_to_pixel (tll->start());
 		double x2 = frame_to_pixel (tll->end());
@@ -1132,21 +1132,21 @@ Editor::update_loop_range_view (bool visibility)
 void
 Editor::update_punch_range_view (bool visibility)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
 	Location* tpl;
 
-	if ((session->config.get_punch_in() || session->config.get_punch_out()) && ((tpl = transport_punch_location()) != 0)) {
+	if ((_session->config.get_punch_in() || _session->config.get_punch_out()) && ((tpl = transport_punch_location()) != 0)) {
 		guint track_canvas_width,track_canvas_height;
 		track_canvas->get_size(track_canvas_width,track_canvas_height);
-		if (session->config.get_punch_in()) {
+		if (_session->config.get_punch_in()) {
 			transport_punch_range_rect->property_x1() = frame_to_pixel (tpl->start());
-			transport_punch_range_rect->property_x2() = (session->config.get_punch_out() ? frame_to_pixel (tpl->end()) : frame_to_pixel (JACK_MAX_FRAMES));
+			transport_punch_range_rect->property_x2() = (_session->config.get_punch_out() ? frame_to_pixel (tpl->end()) : frame_to_pixel (JACK_MAX_FRAMES));
 		} else {
 			transport_punch_range_rect->property_x1() = 0;
-			transport_punch_range_rect->property_x2() = (session->config.get_punch_out() ? frame_to_pixel (tpl->end()) : track_canvas_width);
+			transport_punch_range_rect->property_x2() = (_session->config.get_punch_out() ? frame_to_pixel (tpl->end()) : track_canvas_width);
 		}
 
 		if (visibility) {
@@ -1160,7 +1160,7 @@ Editor::update_punch_range_view (bool visibility)
 void
 Editor::marker_selection_changed ()
 {
-	if (session && session->deletion_in_progress()) {
+	if (_session && _session->deletion_in_progress()) {
 		return;
 	}
 
@@ -1191,10 +1191,10 @@ struct SortLocationsByPosition {
 void
 Editor::goto_nth_marker (int n)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
-	const Locations::LocationList& l (session->locations()->list());
+	const Locations::LocationList& l (_session->locations()->list());
 	Locations::LocationList ordered;
 	ordered = l;
 
@@ -1204,7 +1204,7 @@ Editor::goto_nth_marker (int n)
 	for (Locations::LocationList::iterator i = ordered.begin(); n >= 0 && i != ordered.end(); ++i) {
 		if ((*i)->is_mark() && !(*i)->is_hidden() && !(*i)->is_start()) {
 			if (n == 0) {
-				session->request_locate ((*i)->start(), session->transport_rolling());
+				_session->request_locate ((*i)->start(), _session->transport_rolling());
 				break;
 			}
 			--n;
diff --git a/gtk2_ardour/editor_mixer.cc b/gtk2_ardour/editor_mixer.cc
index 03346dffbc..9decef5a21 100644
--- a/gtk2_ardour/editor_mixer.cc
+++ b/gtk2_ardour/editor_mixer.cc
@@ -75,7 +75,7 @@ Editor::show_editor_mixer (bool yn)
 
 	show_editor_mixer_when_tracks_arrive = false;
 
-	if (!session) {
+	if (!_session) {
 		show_editor_mixer_when_tracks_arrive = yn;
 		return;
 	}
@@ -165,10 +165,10 @@ void
 Editor::create_editor_mixer ()
 {
 	current_mixer_strip = new MixerStrip (*ARDOUR_UI::instance()->the_mixer(),
-					      *session,
+					      _session,
 					      false);
 	current_mixer_strip->Hiding.connect (sigc::mem_fun(*this, &Editor::current_mixer_strip_hidden));
-	current_mixer_strip->GoingAway.connect (sigc::mem_fun(*this, &Editor::current_mixer_strip_removed));
+	scoped_connect (current_mixer_strip->GoingAway, boost::bind (&Editor::current_mixer_strip_removed, this));
 #ifdef GTKOSX
 	current_mixer_strip->WidthChanged.connect (sigc::mem_fun(*this, &Editor::ensure_all_elements_drawn));
 #endif
@@ -180,7 +180,7 @@ Editor::set_selected_mixer_strip (TimeAxisView& view)
 {
 	RouteTimeAxisView* at;
 
-	if (!session || (at = dynamic_cast<RouteTimeAxisView*>(&view)) == 0) {
+	if (!_session || (at = dynamic_cast<RouteTimeAxisView*>(&view)) == 0) {
 		return;
 	}
 
@@ -221,9 +221,9 @@ Editor::update_current_screen ()
 		return;
 	}
 
-	if (session && session->engine().running()) {
+	if (_session && _session->engine().running()) {
 
-		nframes64_t const frame = session->audible_frame();
+		nframes64_t const frame = _session->audible_frame();
 
 		if (_dragging_playhead) {
 			goto almost_done;
@@ -231,7 +231,7 @@ Editor::update_current_screen ()
 
 		/* only update if the playhead is on screen or we are following it */
 
-		if (_follow_playhead && session->requested_return_frame() < 0) {
+		if (_follow_playhead && _session->requested_return_frame() < 0) {
 
 			//playhead_cursor->canvas_item.show();
 
@@ -242,7 +242,7 @@ Editor::update_current_screen ()
 #ifndef  CONTINUOUS_SCROLL
 				if (frame < leftmost_frame || frame > leftmost_frame + current_page_frames()) {
 
-					if (session->transport_speed() < 0) {
+					if (_session->transport_speed() < 0) {
 						if (frame > (current_page_frames()/2)) {
 							center_screen (frame-(current_page_frames()/2));
 						} else {
@@ -261,7 +261,7 @@ Editor::update_current_screen ()
 				   editor canvas
 				*/
 
-				if (session->transport_speed()) {
+				if (_session->transport_speed()) {
 					double target = ((double)frame - (double)current_page_frames()/2.0) / frames_per_unit;
 					if (target <= 0.0) target = 0.0;
 					if ( fabs(target - current) < current_page_frames()/frames_per_unit ) {
@@ -331,9 +331,7 @@ Editor::session_going_away ()
 {
 	_have_idled = false;
 
-	for (vector<sigc::connection>::iterator i = session_connections.begin(); i != session_connections.end(); ++i) {
-		(*i).disconnect ();
-	}
+	_session_connections.drop_connections ();
 
 	stop_scrolling ();
 	selection->clear ();
@@ -389,7 +387,7 @@ Editor::session_going_away ()
 
 	set_title (title.get_string());
 
-	session = 0;
+	SessionHandlePtr::session_going_away ();
 }
 
 void
diff --git a/gtk2_ardour/editor_mouse.cc b/gtk2_ardour/editor_mouse.cc
index cecddd092a..4fb7271c47 100644
--- a/gtk2_ardour/editor_mouse.cc
+++ b/gtk2_ardour/editor_mouse.cc
@@ -970,7 +970,7 @@ Editor::button_press_handler (ArdourCanvas::Item* item, GdkEvent* event, ItemTyp
 
 	track_canvas->grab_focus();
 
-	if (session && session->actively_recording()) {
+	if (_session && _session->actively_recording()) {
 		return true;
 	}
 
@@ -1013,7 +1013,7 @@ Editor::button_release_handler (ArdourCanvas::Item* item, GdkEvent* event, ItemT
 
 	/* no action if we're recording */
 
-	if (session && session->actively_recording()) {
+	if (_session && _session->actively_recording()) {
 		return true;
 	}
 
@@ -1291,7 +1291,7 @@ Editor::button_release_handler (ArdourCanvas::Item* item, GdkEvent* event, ItemT
 				}
 			} else {
 				/* make sure we stop */
-				session->request_transport_speed (0.0);
+				_session->request_transport_speed (0.0);
 			}
 			break;
 
@@ -1681,8 +1681,8 @@ Editor::scrub ()
 
 	if (scrubbing_direction == 0) {
 		/* first move */
-		session->request_locate (_drag->current_pointer_frame(), false);
-		session->request_transport_speed (0.1);
+		_session->request_locate (_drag->current_pointer_frame(), false);
+		_session->request_transport_speed (0.1);
 		scrubbing_direction = 1;
 
 	} else {
@@ -1706,7 +1706,7 @@ Editor::scrub ()
 				scrub_reverse_distance = 0;
 
 				delta = 0.01 * (last_scrub_x - _drag->current_pointer_x());
-				session->request_transport_speed (session->transport_speed() - delta);
+				_session->request_transport_speed (_session->transport_speed() - delta);
 			}
 
 		} else {
@@ -1725,7 +1725,7 @@ Editor::scrub ()
 				scrub_reverse_distance = 0;
 
 				delta = 0.01 * (_drag->current_pointer_x() - last_scrub_x);
-				session->request_transport_speed (session->transport_speed() + delta);
+				_session->request_transport_speed (_session->transport_speed() + delta);
 			}
 		}
 
@@ -1737,11 +1737,11 @@ Editor::scrub ()
 
 			if (scrubbing_direction > 0) {
 				/* was forwards, go backwards */
-				session->request_transport_speed (-0.1);
+				_session->request_transport_speed (-0.1);
 				scrubbing_direction = -1;
 			} else {
 				/* was backwards, go forwards */
-				session->request_transport_speed (0.1);
+				_session->request_transport_speed (0.1);
 				scrubbing_direction = 1;
 			}
 
@@ -1777,7 +1777,7 @@ Editor::motion_handler (ArdourCanvas::Item* /*item*/, GdkEvent* event, bool from
 		step_timeout.disconnect ();
 	}
 
-	if (session && session->actively_recording()) {
+	if (_session && _session->actively_recording()) {
 		/* Sorry. no dragging stuff around while we record */
 		return true;
 	}
@@ -1917,7 +1917,7 @@ Editor::show_verbose_time_cursor (nframes64_t frame, double offset, double xpos,
 	nframes64_t frame_rate;
 	float secs;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -1931,18 +1931,18 @@ Editor::show_verbose_time_cursor (nframes64_t frame, double offset, double xpos,
 
 	switch (m) {
 	case AudioClock::BBT:
-		session->bbt_time (frame, bbt);
+		_session->bbt_time (frame, bbt);
 		snprintf (buf, sizeof (buf), "%02" PRIu32 "|%02" PRIu32 "|%02" PRIu32, bbt.bars, bbt.beats, bbt.ticks);
 		break;
 
 	case AudioClock::Timecode:
-		session->timecode_time (frame, timecode);
+		_session->timecode_time (frame, timecode);
 		snprintf (buf, sizeof (buf), "%02" PRId32 ":%02" PRId32 ":%02" PRId32 ":%02" PRId32, timecode.hours, timecode.minutes, timecode.seconds, timecode.frames);
 		break;
 
 	case AudioClock::MinSec:
 		/* XXX this is copied from show_verbose_duration_cursor() */
-		frame_rate = session->frame_rate();
+		frame_rate = _session->frame_rate();
 		hours = frame / (frame_rate * 3600);
 		frame = frame % (frame_rate * 3600);
 		mins = frame / (frame_rate * 60);
@@ -1974,9 +1974,9 @@ Editor::show_verbose_duration_cursor (nframes64_t start, nframes64_t end, double
 	int hours, mins;
 	nframes64_t distance, frame_rate;
 	float secs;
-	Meter meter_at_start(session->tempo_map().meter_at(start));
+	Meter meter_at_start(_session->tempo_map().meter_at(start));
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -1990,8 +1990,8 @@ Editor::show_verbose_duration_cursor (nframes64_t start, nframes64_t end, double
 
 	switch (m) {
 	case AudioClock::BBT:
-		session->bbt_time (start, sbbt);
-		session->bbt_time (end, ebbt);
+		_session->bbt_time (start, sbbt);
+		_session->bbt_time (end, ebbt);
 
 		/* subtract */
 		/* XXX this computation won't work well if the
@@ -2016,14 +2016,14 @@ Editor::show_verbose_duration_cursor (nframes64_t start, nframes64_t end, double
 		break;
 
 	case AudioClock::Timecode:
-		session->timecode_duration (end - start, timecode);
+		_session->timecode_duration (end - start, timecode);
 		snprintf (buf, sizeof (buf), "%02" PRId32 ":%02" PRId32 ":%02" PRId32 ":%02" PRId32, timecode.hours, timecode.minutes, timecode.seconds, timecode.frames);
 		break;
 
 	case AudioClock::MinSec:
 		/* XXX this stuff should be elsewhere.. */
 		distance = end - start;
-		frame_rate = session->frame_rate();
+		frame_rate = _session->frame_rate();
 		hours = distance / (frame_rate * 3600);
 		distance = distance % (frame_rate * 3600);
 		mins = distance / (frame_rate * 60);
@@ -2255,7 +2255,7 @@ Editor::point_trim (GdkEvent* event)
 					(*i)->region()->trim_front (new_bound, this);
 
 					XMLNode &after = pl->get_state();
-					session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
+					_session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
 				}
 			}
 
@@ -2265,7 +2265,7 @@ Editor::point_trim (GdkEvent* event)
 				XMLNode &before = pl->get_state();
 				rv->region()->trim_front (new_bound, this);
 				XMLNode &after = pl->get_state();
-				session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
+				_session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
 			}
 		}
 
@@ -2284,7 +2284,7 @@ Editor::point_trim (GdkEvent* event)
 					XMLNode &before = pl->get_state();
 					(*i)->region()->trim_end (new_bound, this);
 					XMLNode &after = pl->get_state();
-					session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
+					_session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
 				}
 			}
 
@@ -2295,7 +2295,7 @@ Editor::point_trim (GdkEvent* event)
 				XMLNode &before = pl->get_state();
 				rv->region()->trim_end (new_bound, this);
 				XMLNode &after = pl->get_state();
-				session->add_command (new MementoCommand<Playlist>(*pl.get(), &before, &after));
+				_session->add_command (new MementoCommand<Playlist>(*pl.get(), &before, &after));
 			}
 		}
 
@@ -2418,7 +2418,7 @@ Editor::mouse_brush_insert_region (RegionView* rv, nframes64_t pos)
 	XMLNode &before = playlist->get_state();
 	playlist->add_region (RegionFactory::create (rv->region()), (nframes64_t) (pos * speed));
 	XMLNode &after = playlist->get_state();
-	session->add_command(new MementoCommand<Playlist>(*playlist.get(), &before, &after));
+	_session->add_command(new MementoCommand<Playlist>(*playlist.get(), &before, &after));
 
 	// playlist is frozen, so we have to update manually
 
@@ -2534,7 +2534,7 @@ Editor::start_selection_grab (ArdourCanvas::Item* /*item*/, GdkEvent* event)
 	XMLNode *before = &(playlist->get_state());
 	clicked_routeview->playlist()->add_region (region, selection->time[clicked_selection].start);
 	XMLNode *after = &(playlist->get_state());
-	session->add_command(new MementoCommand<Playlist>(*playlist, before, after));
+	_session->add_command(new MementoCommand<Playlist>(*playlist, before, after));
 
 	commit_reversible_command ();
 
diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index 4ed0354491..2e5556352c 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -96,16 +96,16 @@ using Gtkmm2ext::Keyboard;
 void
 Editor::undo (uint32_t n)
 {
-	if (session) {
-		session->undo (n);
+	if (_session) {
+		_session->undo (n);
 	}
 }
 
 void
 Editor::redo (uint32_t n)
 {
-	if (session) {
-		session->redo (n);
+	if (_session) {
+		_session->redo (n);
 	}
 }
 
@@ -171,7 +171,7 @@ Editor::split_regions_at (nframes64_t where, RegionSelection& regions)
 			XMLNode &before = pl->get_state();
 			pl->split_region ((*a)->region(), where);
 			XMLNode &after = pl->get_state();
-			session->add_command(new MementoCommand<Playlist>(*pl, &before, &after));
+			_session->add_command(new MementoCommand<Playlist>(*pl, &before, &after));
 		}
 
 		a = tmp;
@@ -308,7 +308,7 @@ Editor::nudge_forward (bool next, bool force_playhead)
 
 	get_regions_for_action (rs);
 
-	if (!session) return;
+	if (!_session) return;
 
 	if (!force_playhead && !rs.empty()) {
 
@@ -326,7 +326,7 @@ Editor::nudge_forward (bool next, bool force_playhead)
                         XMLNode &before = r->playlist()->get_state();
 			r->set_position (r->position() + distance, this);
                         XMLNode &after = r->playlist()->get_state();
-			session->add_command (new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
+			_session->add_command (new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
 		}
 
 		commit_reversible_command ();
@@ -368,7 +368,7 @@ Editor::nudge_forward (bool next, bool force_playhead)
 					}
 				}
 				XMLNode& after (loc->get_state());
-				session->add_command (new MementoCommand<Location>(*loc, &before, &after));
+				_session->add_command (new MementoCommand<Location>(*loc, &before, &after));
 			}
 		}
 
@@ -376,7 +376,7 @@ Editor::nudge_forward (bool next, bool force_playhead)
 
 	} else {
 		distance = get_nudge_distance (playhead_cursor->current_frame, next_distance);
-		session->request_locate (playhead_cursor->current_frame + distance);
+		_session->request_locate (playhead_cursor->current_frame + distance);
 	}
 }
 
@@ -389,7 +389,7 @@ Editor::nudge_backward (bool next, bool force_playhead)
 
 	get_regions_for_action (rs);
 
-	if (!session) return;
+	if (!_session) return;
 
 	if (!force_playhead && !rs.empty()) {
 
@@ -412,7 +412,7 @@ Editor::nudge_backward (bool next, bool force_playhead)
 				r->set_position (0, this);
 			}
                         XMLNode &after = r->playlist()->get_state();
-			session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
+			_session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
 		}
 
 		commit_reversible_command ();
@@ -456,7 +456,7 @@ Editor::nudge_backward (bool next, bool force_playhead)
 				}
 
 				XMLNode& after (loc->get_state());
-				session->add_command (new MementoCommand<Location>(*loc, &before, &after));
+				_session->add_command (new MementoCommand<Location>(*loc, &before, &after));
 			}
 		}
 
@@ -467,9 +467,9 @@ Editor::nudge_backward (bool next, bool force_playhead)
 		distance = get_nudge_distance (playhead_cursor->current_frame, next_distance);
 
 		if (playhead_cursor->current_frame > distance) {
-			session->request_locate (playhead_cursor->current_frame - distance);
+			_session->request_locate (playhead_cursor->current_frame - distance);
 		} else {
-			session->goto_start();
+			_session->goto_start();
 		}
 	}
 }
@@ -482,13 +482,13 @@ Editor::nudge_forward_capture_offset ()
 
 	get_regions_for_action (rs);
 
-	if (!session) return;
+	if (!_session) return;
 
 	if (!rs.empty()) {
 
 		begin_reversible_command (_("nudge forward"));
 
-		distance = session->worst_output_latency();
+		distance = _session->worst_output_latency();
 
 		for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 			boost::shared_ptr<Region> r ((*i)->region());
@@ -496,7 +496,7 @@ Editor::nudge_forward_capture_offset ()
 			XMLNode &before = r->playlist()->get_state();
 			r->set_position (r->position() + distance, this);
 			XMLNode &after = r->playlist()->get_state();
-			session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
+			_session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
 		}
 
 		commit_reversible_command ();
@@ -512,13 +512,13 @@ Editor::nudge_backward_capture_offset ()
 
 	get_regions_for_action (rs);
 
-	if (!session) return;
+	if (!_session) return;
 
 	if (!rs.empty()) {
 
 		begin_reversible_command (_("nudge forward"));
 
-		distance = session->worst_output_latency();
+		distance = _session->worst_output_latency();
 
 		for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 			boost::shared_ptr<Region> r ((*i)->region());
@@ -531,7 +531,7 @@ Editor::nudge_backward_capture_offset ()
 				r->set_position (0, this);
 			}
                         XMLNode &after = r->playlist()->get_state();
-			session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
+			_session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
 		}
 
 		commit_reversible_command ();
@@ -543,14 +543,14 @@ Editor::nudge_backward_capture_offset ()
 void
 Editor::move_to_start ()
 {
-	session->goto_start ();
+	_session->goto_start ();
 }
 
 void
 Editor::move_to_end ()
 {
 
-	session->request_locate (session->current_end_frame());
+	_session->request_locate (_session->current_end_frame());
 }
 
 void
@@ -564,7 +564,7 @@ Editor::build_region_boundary_cache ()
 
 	region_boundary_cache.clear ();
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -597,7 +597,7 @@ Editor::build_region_boundary_cache ()
 		tlist = track_views;
 	}
 
-	while (pos < session->current_end_frame() && !at_end) {
+	while (pos < _session->current_end_frame() && !at_end) {
 
 		nframes64_t rpos;
 		nframes64_t lpos = max_frames;
@@ -714,7 +714,7 @@ Editor::find_next_region (nframes64_t frame, RegionPoint point, int32_t dir, Tra
 			break;
 		}
 
-		// rpos is a "track frame", converting it to "session frame"
+		// rpos is a "track frame", converting it to "_session frame"
 		rpos = track_frame_to_session_frame(rpos, track_speed);
 
 		if (rpos > frame) {
@@ -807,7 +807,7 @@ Editor::cursor_to_region_boundary (bool with_selection, int32_t dir)
 	nframes64_t pos = playhead_cursor->current_frame;
 	nframes64_t target;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -821,7 +821,7 @@ Editor::cursor_to_region_boundary (bool with_selection, int32_t dir)
 	}
 
 
-	session->request_locate (target);
+	_session->request_locate (target);
 }
 
 void
@@ -842,7 +842,7 @@ Editor::cursor_to_region_point (EditorCursor* cursor, RegionPoint point, int32_t
 	boost::shared_ptr<Region> r;
 	nframes64_t pos = cursor->current_frame;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -899,7 +899,7 @@ Editor::cursor_to_region_point (EditorCursor* cursor, RegionPoint point, int32_t
 	pos = track_frame_to_session_frame(pos, speed);
 
 	if (cursor == playhead_cursor) {
-		session->request_locate (pos);
+		_session->request_locate (pos);
 	} else {
 		cursor->set_position (pos);
 	}
@@ -943,7 +943,7 @@ Editor::cursor_to_selection_start (EditorCursor *cursor)
 	}
 
 	if (cursor == playhead_cursor) {
-		session->request_locate (pos);
+		_session->request_locate (pos);
 	} else {
 		cursor->set_position (pos);
 	}
@@ -975,7 +975,7 @@ Editor::cursor_to_selection_end (EditorCursor *cursor)
 	}
 
 	if (cursor == playhead_cursor) {
-		session->request_locate (pos);
+		_session->request_locate (pos);
 	} else {
 		cursor->set_position (pos);
 	}
@@ -988,7 +988,7 @@ Editor::selected_marker_to_region_boundary (bool with_selection, int32_t dir)
 	Location* loc;
 	bool ignored;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -1041,7 +1041,7 @@ Editor::selected_marker_to_region_point (RegionPoint point, int32_t dir)
 	Location* loc;
 	bool ignored;
 
-	if (!session || selection->markers.empty()) {
+	if (!_session || selection->markers.empty()) {
 		return;
 	}
 
@@ -1117,7 +1117,7 @@ Editor::selected_marker_to_selection_start ()
 	Location* loc;
 	bool ignored;
 
-	if (!session || selection->markers.empty()) {
+	if (!_session || selection->markers.empty()) {
 		return;
 	}
 
@@ -1156,7 +1156,7 @@ Editor::selected_marker_to_selection_end ()
 	Location* loc;
 	bool ignored;
 
-	if (!session || selection->markers.empty()) {
+	if (!_session || selection->markers.empty()) {
 		return;
 	}
 
@@ -1218,7 +1218,7 @@ Editor::scroll_playhead (bool forward)
 		}
 	}
 
-	session->request_locate (pos);
+	_session->request_locate (pos);
 }
 
 void
@@ -1233,7 +1233,7 @@ Editor::playhead_backward ()
 		cnt = 1;
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate ());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate ());
 		} else {
 			cnt = (nframes64_t) prefix;
 		}
@@ -1252,7 +1252,7 @@ Editor::playhead_backward ()
 	   reload, just to move 1 sample !!!
 	*/
 
-	session->request_locate (pos);
+	_session->request_locate (pos);
 }
 
 void
@@ -1267,7 +1267,7 @@ Editor::playhead_forward ()
 		cnt = 1;
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate ());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate ());
 		} else {
 			cnt = (nframes64_t) floor (prefix);
 		}
@@ -1280,13 +1280,13 @@ Editor::playhead_forward ()
 	   reload, just to move 1 sample !!!
 	*/
 
-	session->request_locate (pos+cnt);
+	_session->request_locate (pos+cnt);
 }
 
 void
 Editor::cursor_align (bool playhead_to_edit)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -1296,7 +1296,7 @@ Editor::cursor_align (bool playhead_to_edit)
 			return;
 		}
 
-		session->request_locate (selection->markers.front()->position(), session->transport_rolling());
+		_session->request_locate (selection->markers.front()->position(), _session->transport_rolling());
 
 	} else {
 		/* move selected markers to playhead */
@@ -1328,7 +1328,7 @@ Editor::edit_cursor_backward ()
 		cnt = 1;
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate ());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate ());
 		} else {
 			cnt = (nframes64_t) prefix;
 		}
@@ -1359,7 +1359,7 @@ Editor::edit_cursor_forward ()
 		cnt = 1;
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate ());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate ());
 		} else {
 			cnt = (nframes64_t) floor (prefix);
 		}
@@ -1381,12 +1381,12 @@ Editor::goto_frame ()
 	}
 
 	if (was_floating) {
-		frame = (nframes64_t) floor (prefix * session->frame_rate());
+		frame = (nframes64_t) floor (prefix * _session->frame_rate());
 	} else {
 		frame = (nframes64_t) floor (prefix);
 	}
 
-	session->request_locate (frame);
+	_session->request_locate (frame);
 }
 
 void
@@ -1402,7 +1402,7 @@ Editor::scroll_backward (float pages)
 		cnt = (nframes64_t) floor (pages * one_page);
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate());
 		} else {
 			cnt = (nframes64_t) floor (prefix * one_page);
 		}
@@ -1430,7 +1430,7 @@ Editor::scroll_forward (float pages)
 		cnt = (nframes64_t) floor (pages * one_page);
 	} else {
 		if (was_floating) {
-			cnt = (nframes64_t) floor (prefix * session->frame_rate());
+			cnt = (nframes64_t) floor (prefix * _session->frame_rate());
 		} else {
 			cnt = (nframes64_t) floor (prefix * one_page);
 		}
@@ -1538,7 +1538,7 @@ Editor::temporal_zoom_step (bool coarser)
 void
 Editor::temporal_zoom (gdouble fpu)
 {
-	if (!session) return;
+	if (!_session) return;
 
 	nframes64_t current_page = current_page_frames();
 	nframes64_t current_leftmost = leftmost_frame;
@@ -1654,7 +1654,7 @@ Editor::temporal_zoom (gdouble fpu)
 
 	}
 
-	// leftmost_after_zoom = min (leftmost_after_zoom, session->current_end_frame());
+	// leftmost_after_zoom = min (leftmost_after_zoom, _session->current_end_frame());
 
 	reposition_and_zoom (leftmost_after_zoom, nfpu);
 }
@@ -1782,15 +1782,15 @@ Editor::temporal_zoom_session ()
 {
 	ENSURE_GUI_THREAD (*this, &Editor::temporal_zoom_session)
 
-	if (session) {
-		temporal_zoom_by_frame (session->current_start_frame(), session->current_end_frame(), "zoom to session");
+	if (_session) {
+		temporal_zoom_by_frame (_session->current_start_frame(), _session->current_end_frame(), "zoom to _session");
 	}
 }
 
 void
 Editor::temporal_zoom_by_frame (nframes64_t start, nframes64_t end, const string & /*op*/)
 {
-	if (!session) return;
+	if (!_session) return;
 
 	if ((start == 0 && end == 0) || end < start) {
 		return;
@@ -1814,7 +1814,7 @@ Editor::temporal_zoom_by_frame (nframes64_t start, nframes64_t end, const string
 void
 Editor::temporal_zoom_to_frame (bool coarser, nframes64_t frame)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 	double range_before = frame - leftmost_frame;
@@ -1840,8 +1840,8 @@ Editor::temporal_zoom_to_frame (bool coarser, nframes64_t frame)
 		new_leftmost = 0;
 	}
 //	begin_reversible_command (_("zoom to frame"));
-//	session->add_undo (sigc::bind (sigc::mem_fun(*this, &Editor::reposition_and_zoom), leftmost_frame, frames_per_unit));
-//	session->add_redo (sigc::bind (sigc::mem_fun(*this, &Editor::reposition_and_zoom), new_leftmost, new_fpu));
+//	_session->add_undo (sigc::bind (sigc::mem_fun(*this, &Editor::reposition_and_zoom), leftmost_frame, frames_per_unit));
+//	_session->add_redo (sigc::bind (sigc::mem_fun(*this, &Editor::reposition_and_zoom), new_leftmost, new_fpu));
 //	commit_reversible_command ();
 
 	reposition_and_zoom (new_leftmost, new_fpu);
@@ -1893,22 +1893,22 @@ Editor::add_location_from_selection ()
 		return;
 	}
 
-	if (session == 0 || clicked_axisview == 0) {
+	if (_session == 0 || clicked_axisview == 0) {
 		return;
 	}
 
 	nframes64_t start = selection->time[clicked_selection].start;
 	nframes64_t end = selection->time[clicked_selection].end;
 
-	session->locations()->next_available_name(rangename,"selection");
+	_session->locations()->next_available_name(rangename,"selection");
 	Location *location = new Location (start, end, rangename, Location::IsRangeMarker);
 
-	session->begin_reversible_command (_("add marker"));
-        XMLNode &before = session->locations()->get_state();
-	session->locations()->add (location, true);
-        XMLNode &after = session->locations()->get_state();
-	session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	_session->begin_reversible_command (_("add marker"));
+        XMLNode &before = _session->locations()->get_state();
+	_session->locations()->add (location, true);
+        XMLNode &after = _session->locations()->get_state();
+	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 }
 
 void
@@ -1918,23 +1918,23 @@ Editor::add_location_mark (nframes64_t where)
 
 	select_new_marker = true;
 
-	session->locations()->next_available_name(markername,"mark");
+	_session->locations()->next_available_name(markername,"mark");
 	if (!choose_new_marker_name(markername)) {
 		return;
 	}
 	Location *location = new Location (where, where, markername, Location::IsMark);
-	session->begin_reversible_command (_("add marker"));
-        XMLNode &before = session->locations()->get_state();
-	session->locations()->add (location, true);
-        XMLNode &after = session->locations()->get_state();
-	session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	_session->begin_reversible_command (_("add marker"));
+        XMLNode &before = _session->locations()->get_state();
+	_session->locations()->add (location, true);
+        XMLNode &after = _session->locations()->get_state();
+	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 }
 
 void
 Editor::add_location_from_playhead_cursor ()
 {
-	add_location_mark (session->audible_frame());
+	add_location_mark (_session->audible_frame());
 }
 
 void
@@ -1948,8 +1948,8 @@ Editor::add_locations_from_audio_region ()
 		return;
 	}
 
-	session->begin_reversible_command (rs.size () > 1 ? _("add markers") : _("add marker"));
-	XMLNode &before = session->locations()->get_state();
+	_session->begin_reversible_command (rs.size () > 1 ? _("add markers") : _("add marker"));
+	XMLNode &before = _session->locations()->get_state();
 
 	cerr << "Add locations\n";
 
@@ -1959,12 +1959,12 @@ Editor::add_locations_from_audio_region ()
 
 		Location *location = new Location (region->position(), region->last_frame(), region->name(), Location::IsRangeMarker);
 
-		session->locations()->add (location, true);
+		_session->locations()->add (location, true);
 	}
 
-	XMLNode &after = session->locations()->get_state();
-	session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	XMLNode &after = _session->locations()->get_state();
+	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 }
 
 void
@@ -1978,13 +1978,13 @@ Editor::add_location_from_audio_region ()
 		return;
 	}
 
-	session->begin_reversible_command (_("add marker"));
-	XMLNode &before = session->locations()->get_state();
+	_session->begin_reversible_command (_("add marker"));
+	XMLNode &before = _session->locations()->get_state();
 
 	string markername;
 
 	if (rs.size() > 1) {		// more than one region selected
-		session->locations()->next_available_name(markername, "regions");
+		_session->locations()->next_available_name(markername, "regions");
 	} else {
 		RegionView* rv = *(rs.begin());
 		boost::shared_ptr<Region> region = rv->region();
@@ -1999,11 +1999,11 @@ Editor::add_location_from_audio_region ()
 
 	// single range spanning all selected
 	Location *location = new Location (rs.start(), rs.end_frame(), markername, Location::IsRangeMarker);
-	session->locations()->add (location, true);
+	_session->locations()->add (location, true);
 
-	XMLNode &after = session->locations()->get_state();
-	session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	XMLNode &after = _session->locations()->get_state();
+	_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 }
 
 void
@@ -2064,32 +2064,32 @@ Editor::search_forwards ()
 void
 Editor::jump_forward_to_mark ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	Location *location = session->locations()->first_location_after (playhead_cursor->current_frame);
+	Location *location = _session->locations()->first_location_after (playhead_cursor->current_frame);
 
 	if (location) {
-		session->request_locate (location->start(), session->transport_rolling());
+		_session->request_locate (location->start(), _session->transport_rolling());
 	} else {
-		session->request_locate (session->current_end_frame());
+		_session->request_locate (_session->current_end_frame());
 	}
 }
 
 void
 Editor::jump_backward_to_mark ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	Location *location = session->locations()->first_location_before (playhead_cursor->current_frame);
+	Location *location = _session->locations()->first_location_before (playhead_cursor->current_frame);
 
 	if (location) {
-		session->request_locate (location->start(), session->transport_rolling());
+		_session->request_locate (location->start(), _session->transport_rolling());
 	} else {
-		session->goto_start ();
+		_session->goto_start ();
 	}
 }
 
@@ -2102,66 +2102,66 @@ Editor::set_mark ()
 	string markername;
 
 	if (get_prefix (prefix, was_floating)) {
-		pos = session->audible_frame ();
+		pos = _session->audible_frame ();
 	} else {
 		if (was_floating) {
-			pos = (nframes64_t) floor (prefix * session->frame_rate ());
+			pos = (nframes64_t) floor (prefix * _session->frame_rate ());
 		} else {
 			pos = (nframes64_t) floor (prefix);
 		}
 	}
 
-	session->locations()->next_available_name(markername,"mark");
+	_session->locations()->next_available_name(markername,"mark");
 	if (!choose_new_marker_name(markername)) {
 		return;
 	}
-	session->locations()->add (new Location (pos, 0, markername, Location::IsMark), true);
+	_session->locations()->add (new Location (pos, 0, markername, Location::IsMark), true);
 }
 
 void
 Editor::clear_markers ()
 {
-	if (session) {
-		session->begin_reversible_command (_("clear markers"));
-                XMLNode &before = session->locations()->get_state();
-		session->locations()->clear_markers ();
-                XMLNode &after = session->locations()->get_state();
-		session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-		session->commit_reversible_command ();
+	if (_session) {
+		_session->begin_reversible_command (_("clear markers"));
+                XMLNode &before = _session->locations()->get_state();
+		_session->locations()->clear_markers ();
+                XMLNode &after = _session->locations()->get_state();
+		_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+		_session->commit_reversible_command ();
 	}
 }
 
 void
 Editor::clear_ranges ()
 {
-	if (session) {
-		session->begin_reversible_command (_("clear ranges"));
-                XMLNode &before = session->locations()->get_state();
+	if (_session) {
+		_session->begin_reversible_command (_("clear ranges"));
+                XMLNode &before = _session->locations()->get_state();
 
-		Location * looploc = session->locations()->auto_loop_location();
-		Location * punchloc = session->locations()->auto_punch_location();
+		Location * looploc = _session->locations()->auto_loop_location();
+		Location * punchloc = _session->locations()->auto_punch_location();
 
-		session->locations()->clear_ranges ();
+		_session->locations()->clear_ranges ();
 		// re-add these
-		if (looploc) session->locations()->add (looploc);
-		if (punchloc) session->locations()->add (punchloc);
+		if (looploc) _session->locations()->add (looploc);
+		if (punchloc) _session->locations()->add (punchloc);
 
-                XMLNode &after = session->locations()->get_state();
-		session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-		session->commit_reversible_command ();
+                XMLNode &after = _session->locations()->get_state();
+		_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+		_session->commit_reversible_command ();
 	}
 }
 
 void
 Editor::clear_locations ()
 {
-	session->begin_reversible_command (_("clear locations"));
-        XMLNode &before = session->locations()->get_state();
-	session->locations()->clear ();
-        XMLNode &after = session->locations()->get_state();
-	session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
-	session->locations()->clear ();
+	_session->begin_reversible_command (_("clear locations"));
+        XMLNode &before = _session->locations()->get_state();
+	_session->locations()->clear ();
+        XMLNode &after = _session->locations()->get_state();
+	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
+	_session->locations()->clear ();
 }
 
 void
@@ -2231,7 +2231,7 @@ Editor::insert_region_list_drag (boost::shared_ptr<Region> region, int x, int y)
 	begin_reversible_command (_("insert dragged region"));
         XMLNode &before = playlist->get_state();
 	playlist->add_region (RegionFactory::create (region), where, 1.0);
-	session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+	_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 	commit_reversible_command ();
 }
 
@@ -2309,7 +2309,7 @@ Editor::insert_region_list_selection (float times)
 	begin_reversible_command (_("insert region"));
 	XMLNode &before = playlist->get_state();
 	playlist->add_region ((RegionFactory::create (region)), get_preferred_edit_position(), times);
-	session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+	_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 	commit_reversible_command ();
 }
 
@@ -2333,12 +2333,12 @@ Editor::edit_envelope ()
 void
 Editor::transition_to_rolling (bool fwd)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	if (session->config.get_external_sync()) {
-		switch (session->config.get_sync_source()) {
+	if (_session->config.get_external_sync()) {
+		switch (_session->config.get_sync_source()) {
 		case JACK:
 			break;
 		default:
@@ -2347,24 +2347,24 @@ Editor::transition_to_rolling (bool fwd)
 		}
 	}
 
-	if (session->is_auditioning()) {
-		session->cancel_audition ();
+	if (_session->is_auditioning()) {
+		_session->cancel_audition ();
 		return;
 	}
 
-	session->request_transport_speed (fwd ? 1.0f : -1.0f);
+	_session->request_transport_speed (fwd ? 1.0f : -1.0f);
 }
 
 void
 Editor::play_from_start ()
 {
-	session->request_locate (session->current_start_frame(), true);
+	_session->request_locate (_session->current_start_frame(), true);
 }
 
 void
 Editor::play_from_edit_point ()
 {
-	session->request_locate (get_preferred_edit_position(), true);
+	_session->request_locate (get_preferred_edit_position(), true);
 }
 
 void
@@ -2375,19 +2375,19 @@ Editor::play_from_edit_point_and_return ()
 
 	start_frame = get_preferred_edit_position (true);
 
-	if (session->transport_rolling()) {
-		session->request_locate (start_frame, false);
+	if (_session->transport_rolling()) {
+		_session->request_locate (start_frame, false);
 		return;
 	}
 
 	/* don't reset the return frame if its already set */
 
-	if ((return_frame = session->requested_return_frame()) < 0) {
-		return_frame = session->audible_frame();
+	if ((return_frame = _session->requested_return_frame()) < 0) {
+		return_frame = _session->audible_frame();
 	}
 
 	if (start_frame >= 0) {
-		session->request_roll_at_and_return (start_frame, return_frame);
+		_session->request_roll_at_and_return (start_frame, return_frame);
 	}
 }
 
@@ -2398,7 +2398,7 @@ Editor::play_selection ()
 		return;
 	}
 
-	session->request_play_range (&selection->time, true);
+	_session->request_play_range (&selection->time, true);
 }
 
 void
@@ -2418,9 +2418,9 @@ Editor::loop_selected_region ()
 
 			// enable looping, reposition and start rolling
 
-			session->request_play_loop (true);
-			session->request_locate (tll->start(), false);
-			session->request_transport_speed (1.0f);
+			_session->request_play_loop (true);
+			_session->request_locate (tll->start(), false);
+			_session->request_transport_speed (1.0f);
 		}
 	}
 }
@@ -2432,7 +2432,7 @@ Editor::play_location (Location& location)
 		return;
 	}
 
-	session->request_bounded_roll (location.start(), location.end());
+	_session->request_bounded_roll (location.start(), location.end());
 }
 
 void
@@ -2448,8 +2448,8 @@ Editor::loop_location (Location& location)
 		tll->set (location.start(), location.end());
 
 		// enable looping, reposition and start rolling
-		session->request_play_loop (true);
-		session->request_locate (tll->start(), true);
+		_session->request_play_loop (true);
+		_session->request_locate (tll->start(), true);
 	}
 }
 
@@ -2546,8 +2546,8 @@ Editor::rename_region()
 void
 Editor::audition_playlist_region_via_route (boost::shared_ptr<Region> region, Route& route)
 {
-	if (session->is_auditioning()) {
-		session->cancel_audition ();
+	if (_session->is_auditioning()) {
+		_session->cancel_audition ();
 	}
 
 	// note: some potential for creativity here, because region doesn't
@@ -2557,7 +2557,7 @@ Editor::audition_playlist_region_via_route (boost::shared_ptr<Region> region, Ro
 
 	route.set_solo (true, this);
 
-	session->request_bounded_roll (region->position(), region->position() + region->length());
+	_session->request_bounded_roll (region->position(), region->position() + region->length());
 
 	/* XXX how to unset the solo state ? */
 }
@@ -2569,7 +2569,7 @@ Editor::play_edit_range ()
 	nframes64_t start, end;
 
 	if (get_edit_op_range (start, end)) {
-		session->request_bounded_roll (start, end);
+		_session->request_bounded_roll (start, end);
 	}
 }
 
@@ -2595,13 +2595,13 @@ Editor::play_selected_region ()
 		}
 	}
 
-	session->request_bounded_roll (start, end);
+	_session->request_bounded_roll (start, end);
 }
 
 void
 Editor::audition_playlist_region_standalone (boost::shared_ptr<Region> region)
 {
-	session->audition_region (region);
+	_session->audition_region (region);
 }
 
 void
@@ -2670,7 +2670,7 @@ Editor::region_from_selection ()
 		}
 
 		internal_start = start - current->position();
-		session->region_name (new_name, current->name(), true);
+		_session->region_name (new_name, current->name(), true);
 		boost::shared_ptr<Region> region (RegionFactory::create (current,
 				internal_start, selection_cnt, new_name));
 	}
@@ -2703,7 +2703,7 @@ Editor::create_region_from_selection (vector<boost::shared_ptr<Region> >& new_re
 		}
 
 		internal_start = start - current->position();
-		session->region_name (new_name, current->name(), true);
+		_session->region_name (new_name, current->name(), true);
 
 		new_regions.push_back (RegionFactory::create (current,
 					internal_start, end - start + 1, new_name));
@@ -2724,7 +2724,7 @@ Editor::split_multichannel_region ()
 	vector< boost::shared_ptr<Region> > v;
 
 	for (list<RegionView*>::iterator x = rs.begin(); x != rs.end(); ++x) {
-		(*x)->region()->separate_by_channel (*session, v);
+		(*x)->region()->separate_by_channel (*_session, v);
 	}
 }
 
@@ -2845,7 +2845,7 @@ Editor::separate_regions_between (const TimeSelection& ts)
 								in_command = true;
 							}
 
-							session->add_command(new MementoCommand<Playlist>(
+							_session->add_command(new MementoCommand<Playlist>(
 									*playlist, before, &playlist->get_state()));
 						}
 					}
@@ -2901,7 +2901,7 @@ Editor::separate_region_from_selection ()
 void
 Editor::separate_region_from_punch ()
 {
-	Location* loc  = session->locations()->auto_punch_location();
+	Location* loc  = _session->locations()->auto_punch_location();
 	if (loc) {
 		separate_regions_using_location (*loc);
 	}
@@ -2910,7 +2910,7 @@ Editor::separate_region_from_punch ()
 void
 Editor::separate_region_from_loop ()
 {
-	Location* loc  = session->locations()->auto_loop_location();
+	Location* loc  = _session->locations()->auto_loop_location();
 	if (loc) {
 		separate_regions_using_location (*loc);
 	}
@@ -3017,7 +3017,7 @@ Editor::crop_region_to (nframes64_t start, nframes64_t end)
 		XMLNode &before = (*i)->get_state();
 		region->trim_to (the_start, cnt, this);
 		XMLNode &after = (*i)->get_state();
-		session->add_command (new MementoCommand<Playlist>(*(*i), &before, &after));
+		_session->add_command (new MementoCommand<Playlist>(*(*i), &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -3031,11 +3031,11 @@ Editor::region_fill_track ()
 
 	get_regions_for_action (rs);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	end = session->current_end_frame ();
+	end = _session->current_end_frame ();
 
 	begin_reversible_command (_("region fill"));
 
@@ -3057,7 +3057,7 @@ Editor::region_fill_track ()
 
 		XMLNode &before = pl->get_state();
 		pl->add_region (RegionFactory::create (region), region->last_frame(), times);
-		session->add_command (new MementoCommand<Playlist>(*pl, &before, &pl->get_state()));
+		_session->add_command (new MementoCommand<Playlist>(*pl, &before, &pl->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -3101,7 +3101,7 @@ Editor::region_fill_selection ()
 
                 XMLNode &before = playlist->get_state();
 		playlist->add_region (RegionFactory::create (region), start, times);
-		session->add_command (new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+		_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -3137,7 +3137,7 @@ Editor::set_sync_point (nframes64_t where, const RegionSelection& rs)
 		XMLNode &before = region->playlist()->get_state();
 		region->set_sync_position (where);
 		XMLNode &after = region->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
 	}
 
 	if (in_command) {
@@ -3163,7 +3163,7 @@ Editor::remove_region_sync ()
                 XMLNode &before = (*i)->region()->playlist()->get_state();
 		(*i)->region()->clear_sync_position ();
                 XMLNode &after = (*i)->region()->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(*((*i)->region()->playlist()), &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*((*i)->region()->playlist()), &before, &after));
 	}
 	commit_reversible_command ();
 }
@@ -3184,7 +3184,7 @@ Editor::naturalize ()
                 XMLNode &before = (*i)->region()->get_state();
 		(*i)->region()->move_to_natural_position (this);
                 XMLNode &after = (*i)->region()->get_state();
-		session->add_command (new MementoCommand<Region>(*((*i)->region().get()), &before, &after));
+		_session->add_command (new MementoCommand<Region>(*((*i)->region().get()), &before, &after));
 	}
 	commit_reversible_command ();
 }
@@ -3286,7 +3286,7 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 	XMLNode &before = r->playlist()->get_state();
 	r->set_position (pos, this);
 	XMLNode &after = r->playlist()->get_state();
-	session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
+	_session->add_command(new MementoCommand<Playlist>(*(r->playlist()), &before, &after));
 
 	/* move rest by the same amount */
 
@@ -3305,7 +3305,7 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 		}
 
                 XMLNode &after = region->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
 
 	}
 
@@ -3358,7 +3358,7 @@ Editor::align_region_internal (boost::shared_ptr<Region> region, RegionPoint poi
 	}
 
 	XMLNode &after = region->playlist()->get_state();
-	session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
+	_session->add_command(new MementoCommand<Playlist>(*(region->playlist()), &before, &after));
 }
 
 void
@@ -3397,7 +3397,7 @@ Editor::trim_region (bool front)
 				(*i)->region()->trim_end (where, this);
 			}
 			XMLNode &after = pl->get_state();
-			session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
+			_session->add_command(new MementoCommand<Playlist>(*pl.get(), &before, &after));
 		}
 	}
 
@@ -3408,7 +3408,7 @@ Editor::trim_region (bool front)
 void
 Editor::trim_region_to_loop ()
 {
-	Location* loc = session->locations()->auto_loop_location();
+	Location* loc = _session->locations()->auto_loop_location();
 	if (!loc) {
 		return;
 	}
@@ -3418,7 +3418,7 @@ Editor::trim_region_to_loop ()
 void
 Editor::trim_region_to_punch ()
 {
-	Location* loc = session->locations()->auto_punch_location();
+	Location* loc = _session->locations()->auto_punch_location();
 	if (!loc) {
 		return;
 	}
@@ -3463,7 +3463,7 @@ Editor::trim_region_to_location (const Location& loc, const char* str)
 		XMLNode &before = rv->region()->playlist()->get_state();
 		rv->region()->trim_to (start, (end - start), this);
 		XMLNode &after = rv->region()->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(
+		_session->add_command(new MementoCommand<Playlist>(
 				*(rv->region()->playlist()), &before, &after));
 	}
 
@@ -3501,9 +3501,9 @@ Editor::trim_region_to_edit_point ()
 		}
 
 		XMLNode &before = rv->region()->playlist()->get_state();
-		rv->region()->trim_end( session_frame_to_track_frame(where, speed), this);
+		rv->region()->trim_end (session_frame_to_track_frame(where, speed), this);
 		XMLNode &after = rv->region()->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(
+		_session->add_command(new MementoCommand<Playlist>(
 				*(rv->region()->playlist()), &before, &after));
 	}
 
@@ -3541,9 +3541,9 @@ Editor::trim_region_from_edit_point ()
 		}
 
 		XMLNode &before = rv->region()->playlist()->get_state();
-		rv->region()->trim_front ( session_frame_to_track_frame(where, speed), this);
+		rv->region()->trim_front (session_frame_to_track_frame(where, speed), this);
 		XMLNode &after = rv->region()->playlist()->get_state();
-		session->add_command(new MementoCommand<Playlist>(
+		_session->add_command(new MementoCommand<Playlist>(
 				*(rv->region()->playlist()), &before, &after));
 	}
 
@@ -3623,7 +3623,7 @@ Editor::trim_to_region(bool forward)
 		}
 
 		XMLNode &after = playlist->get_state();
-		session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
+		_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -3750,7 +3750,7 @@ Editor::bounce_range_selection (bool replace, bool enable_processing)
 		}
 
                 XMLNode &after = playlist->get_state();
-		session->add_command (new MementoCommand<Playlist> (*playlist, &before, &after));
+		_session->add_command (new MementoCommand<Playlist> (*playlist, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -3842,7 +3842,7 @@ Editor::cut_copy (CutCopyOp op)
 		bool ignored;
 		Location* loc = find_location_from_marker (entered_marker, ignored);
 
-		if (session && loc) {
+		if (_session && loc) {
 			Glib::signal_idle().connect (sigc::bind (sigc::mem_fun(*this, &Editor::really_remove_marker), loc));
 		}
 
@@ -3944,7 +3944,7 @@ Editor::cut_copy_points (CutCopyOp op)
 {
 	for (PointSelection::iterator i = selection->points.begin(); i != selection->points.end(); ++i) {
 
-		AutomationTimeAxisView* atv = dynamic_cast<AutomationTimeAxisView*>(&(*i).track);
+		AutomationTimeAxisView* atv = dynamic_cast<AutomationTimeAxisView*>((*i).track);
 
 		if (atv) {
 			atv->cut_copy_clear_objects (selection->points, op);
@@ -3996,7 +3996,7 @@ Editor::remove_clicked_region ()
         XMLNode &before = playlist->get_state();
 	playlist->remove_region (clicked_regionview->region());
         XMLNode &after = playlist->get_state();
-	session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
+	_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
 	commit_reversible_command ();
 }
 
@@ -4008,7 +4008,7 @@ Editor::remove_selected_regions ()
 	RegionSelection rs;
 	get_regions_for_action (rs);
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4070,7 +4070,7 @@ Editor::remove_selected_regions ()
 
 	for (pl = playlists.begin(); pl != playlists.end(); ++pl) {
 		(*pl).playlist->thaw ();
-		session->add_command(new MementoCommand<Playlist>(*(*pl).playlist, (*pl).before, &(*pl).playlist->get_state()));
+		_session->add_command(new MementoCommand<Playlist>(*(*pl).playlist, (*pl).before, &(*pl).playlist->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -4165,7 +4165,7 @@ Editor::cut_copy_regions (CutCopyOp op, RegionSelection& rs)
 		assert (z != pmap.end());
 
 		if (!(*z).pl) {
-			npl = PlaylistFactory::create (pl->data_type(), *session, "cutlist", true);
+			npl = PlaylistFactory::create (pl->data_type(), *_session, "cutlist", true);
 			npl->freeze();
 			(*z).pl = npl;
 		} else {
@@ -4213,7 +4213,7 @@ Editor::cut_copy_regions (CutCopyOp op, RegionSelection& rs)
 
 	for (set<PlaylistState, lt_playlist>::iterator pl = freezelist.begin(); pl != freezelist.end(); ++pl) {
 		(*pl).playlist->thaw ();
-		session->add_command (new MementoCommand<Playlist>(*(*pl).playlist, (*pl).before, &(*pl).playlist->get_state()));
+		_session->add_command (new MementoCommand<Playlist>(*(*pl).playlist, (*pl).before, &(*pl).playlist->get_state()));
 	}
 }
 
@@ -4352,7 +4352,7 @@ Editor::duplicate_some_regions (RegionSelection& regions, float times)
  		playlist = (*i)->region()->playlist();
                 XMLNode &before = playlist->get_state();
 		playlist->duplicate (r, end_frame + (r->first_frame() - start_frame) + 1, times);
-		session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+		_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 
 		c.disconnect ();
 
@@ -4394,7 +4394,7 @@ Editor::duplicate_selection (float times)
 		XMLNode &before = playlist->get_state();
 		playlist->duplicate (*ri, selection->time[clicked_selection].end, times);
 		XMLNode &after = playlist->get_state();
-		session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
+		_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
 
 		++ri;
 		if (ri == new_regions.end()) {
@@ -4412,7 +4412,7 @@ Editor::reset_point_selection ()
 
 	for (PointSelection::iterator i = selection->points.begin(); i != selection->points.end(); ++i) {
 
-		AutomationTimeAxisView* atv = dynamic_cast<AutomationTimeAxisView*>(&(*i).track);
+		AutomationTimeAxisView* atv = dynamic_cast<AutomationTimeAxisView*>((*i).track);
 
 		if (atv) {
 			atv->reset_objects (selection->points);
@@ -4441,7 +4441,7 @@ Editor::clear_playlist (boost::shared_ptr<Playlist> playlist)
         XMLNode &before = playlist->get_state();
 	playlist->clear ();
         XMLNode &after = playlist->get_state();
-	session->add_command (new MementoCommand<Playlist>(*playlist.get(), &before, &after));
+	_session->add_command (new MementoCommand<Playlist>(*playlist.get(), &before, &after));
 	commit_reversible_command ();
 }
 
@@ -4478,7 +4478,7 @@ Editor::nudge_track (bool use_edit, bool forwards)
                 XMLNode &before = playlist->get_state();
 		playlist->nudge_after (start, distance, forwards);
                 XMLNode &after = playlist->get_state();
-		session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
+		_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -4490,7 +4490,7 @@ Editor::remove_last_capture ()
 	vector<string> choices;
 	string prompt;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4504,18 +4504,18 @@ Editor::remove_last_capture ()
 		Gtkmm2ext::Choice prompter (prompt, choices);
 
 		if (prompter.run () == 1) {
-			session->remove_last_capture ();
+			_session->remove_last_capture ();
 		}
 
 	} else {
-		session->remove_last_capture();
+		_session->remove_last_capture();
 	}
 }
 
 void
 Editor::normalize_region ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4556,7 +4556,7 @@ Editor::normalize_region ()
 			continue;
  		XMLNode &before = arv->region()->get_state();
 		arv->audio_region()->normalize_to (spin.get_value());
-		session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
+		_session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -4569,7 +4569,7 @@ Editor::normalize_region ()
 void
 Editor::reset_region_scale_amplitude ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4589,7 +4589,7 @@ Editor::reset_region_scale_amplitude ()
 			continue;
 		XMLNode &before = arv->region()->get_state();
 		arv->audio_region()->set_scale_amplitude (1.0f);
-		session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
+		_session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -4598,7 +4598,7 @@ Editor::reset_region_scale_amplitude ()
 void
 Editor::adjust_region_scale_amplitude (bool up)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4639,7 +4639,7 @@ Editor::adjust_region_scale_amplitude (bool up)
 		}
 
 		arv->audio_region()->set_scale_amplitude (fraction);
-		session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
+		_session->add_command (new MementoCommand<Region>(*(arv->region().get()), &before, &arv->region()->get_state()));
 	}
 
 	commit_reversible_command ();
@@ -4649,18 +4649,18 @@ Editor::adjust_region_scale_amplitude (bool up)
 void
 Editor::reverse_region ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	Reverse rev (*session);
+	Reverse rev (*_session);
 	apply_filter (rev, _("reverse regions"));
 }
 
 void
 Editor::strip_region_silence ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4684,7 +4684,7 @@ Editor::strip_region_silence ()
 	int const r = d.run ();
 
 	if (r == Gtk::RESPONSE_OK) {
-		StripSilence s (*session, d.threshold (), d.minimum_length (), d.fade_length ());
+		StripSilence s (*_session, d.threshold (), d.minimum_length (), d.fade_length ());
 		apply_filter (s, _("strip silence"));
 	}
 }
@@ -4725,7 +4725,7 @@ Editor::apply_midi_note_edit_op (MidiOperator& op)
 			cmd = apply_midi_note_edit_op_to_region (op, *mrv);
 			if (cmd) {
 				(*cmd)();
-				session->add_command (cmd);
+				_session->add_command (cmd);
 			}
 		}
 
@@ -4739,7 +4739,7 @@ Editor::apply_midi_note_edit_op (MidiOperator& op)
 void
 Editor::quantize_region ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -4750,7 +4750,7 @@ Editor::quantize_region ()
 	qd->hide ();
 
 	if (r == Gtk::RESPONSE_OK) {
-		Quantize quant (*session, Plain,
+		Quantize quant (*_session, Plain,
 				qd->snap_start(), qd->snap_end(),
 				qd->start_grid_size(), qd->end_grid_size(),
 				qd->strength(), qd->swing(), qd->threshold());
@@ -4809,7 +4809,7 @@ Editor::apply_filter (Filter& filter, string command)
 				}
 
 				XMLNode &after = playlist->get_state();
-				session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
+				_session->add_command(new MementoCommand<Playlist>(*playlist, &before, &after));
 			} else {
 				goto out;
 			}
@@ -4883,11 +4883,11 @@ Editor::reset_region_gain_envelopes ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("reset region gain"));
+	_session->begin_reversible_command (_("reset region gain"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
@@ -4896,11 +4896,11 @@ Editor::reset_region_gain_envelopes ()
 			XMLNode& before (alist->get_state());
 
 			arv->audio_region()->set_default_envelope ();
-			session->add_command (new MementoCommand<AutomationList>(*arv->audio_region()->envelope().get(), &before, &alist->get_state()));
+			_session->add_command (new MementoCommand<AutomationList>(*arv->audio_region()->envelope().get(), &before, &alist->get_state()));
 		}
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -4908,11 +4908,11 @@ Editor::toggle_gain_envelope_visibility ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region gain envelope visible"));
+	_session->begin_reversible_command (_("region gain envelope visible"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
@@ -4920,11 +4920,11 @@ Editor::toggle_gain_envelope_visibility ()
 			XMLNode &before = arv->region()->get_state ();
 			arv->set_envelope_visible (!arv->envelope_visible());
 			XMLNode &after = arv->region()->get_state ();
-			session->add_command (new MementoCommand<Region> (*(arv->region().get()), &before, &after));
+			_session->add_command (new MementoCommand<Region> (*(arv->region().get()), &before, &after));
 		}
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -4932,11 +4932,11 @@ Editor::toggle_gain_envelope_active ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region gain envelope active"));
+	_session->begin_reversible_command (_("region gain envelope active"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		AudioRegionView* const arv = dynamic_cast<AudioRegionView*>(*i);
@@ -4944,11 +4944,11 @@ Editor::toggle_gain_envelope_active ()
 			XMLNode &before = arv->region()->get_state ();
 			arv->audio_region()->set_envelope_active (!arv->audio_region()->envelope_active());
 			XMLNode &after = arv->region()->get_state ();
-			session->add_command (new MementoCommand<Region> (*(arv->region().get()), &before, &after));
+			_session->add_command (new MementoCommand<Region> (*(arv->region().get()), &before, &after));
 		}
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -4956,20 +4956,20 @@ Editor::toggle_region_lock ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region lock"));
+	_session->begin_reversible_command (_("region lock"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		XMLNode &before = (*i)->region()->get_state ();
 		(*i)->region()->set_locked (!(*i)->region()->locked());
 		XMLNode &after = (*i)->region()->get_state ();
-		session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
+		_session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -4977,20 +4977,20 @@ Editor::set_region_lock_style (Region::PositionLockStyle ps)
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region lock style"));
+	_session->begin_reversible_command (_("region lock style"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		XMLNode &before = (*i)->region()->get_state ();
 		(*i)->region()->set_position_lock_style (ps);
 		XMLNode &after = (*i)->region()->get_state ();
-		session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
+		_session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 
@@ -4999,20 +4999,20 @@ Editor::toggle_region_mute ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region mute"));
+	_session->begin_reversible_command (_("region mute"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		XMLNode &before = (*i)->region()->get_state ();
 		(*i)->region()->set_muted (!(*i)->region()->muted());
 		XMLNode &after = (*i)->region()->get_state ();
-		session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
+		_session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -5020,20 +5020,20 @@ Editor::toggle_region_opaque ()
 {
 	RegionSelection rs = get_equivalent_regions (selection->regions, RouteGroup::Edit);
 
-	if (!session || rs.empty()) {
+	if (!_session || rs.empty()) {
 		return;
 	}
 
-	session->begin_reversible_command (_("region opacity"));
+	_session->begin_reversible_command (_("region opacity"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ++i) {
 		XMLNode &before = (*i)->region()->get_state ();
 		(*i)->region()->set_opaque (!(*i)->region()->opaque());
 		XMLNode &after = (*i)->region()->get_state ();
-		session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
+		_session->add_command (new MementoCommand<Region> (*((*i)->region().get()), &before, &after));
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
@@ -5125,7 +5125,7 @@ Editor::set_fade_length (bool in)
 		}
 
 		XMLNode &after = alist->get_state();
-		session->add_command(new MementoCommand<AutomationList>(*alist, &before, &after));
+		_session->add_command(new MementoCommand<AutomationList>(*alist, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5175,7 +5175,7 @@ Editor::toggle_fade_active (bool in)
 			region->set_fade_out_active (!yn);
 		}
 		XMLNode &after = region->get_state();
-		session->add_command(new MementoCommand<AudioRegion>(*region.get(), &before, &after));
+		_session->add_command(new MementoCommand<AudioRegion>(*region.get(), &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5207,7 +5207,7 @@ Editor::set_fade_in_shape (AudioRegion::FadeShape shape)
 		tmp->audio_region()->set_fade_in_shape (shape);
 
 		XMLNode &after = alist->get_state();
-		session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
+		_session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5240,7 +5240,7 @@ Editor::set_fade_out_shape (AudioRegion::FadeShape shape)
 		tmp->audio_region()->set_fade_out_shape (shape);
 
 		XMLNode &after = alist->get_state();
-		session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
+		_session->add_command(new MementoCommand<AutomationList>(*alist.get(), &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5274,7 +5274,7 @@ Editor::set_fade_in_active (bool yn)
 		ar->set_fade_in_active (yn);
 
 		XMLNode &after = ar->get_state();
-		session->add_command(new MementoCommand<AudioRegion>(*ar, &before, &after));
+		_session->add_command(new MementoCommand<AudioRegion>(*ar, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5307,7 +5307,7 @@ Editor::set_fade_out_active (bool yn)
 		ar->set_fade_out_active (yn);
 
 		XMLNode &after = ar->get_state();
-		session->add_command(new MementoCommand<AudioRegion>(*ar, &before, &after));
+		_session->add_command(new MementoCommand<AudioRegion>(*ar, &before, &after));
 	}
 
 	commit_reversible_command ();
@@ -5363,7 +5363,7 @@ Editor::toggle_selected_region_fades (int dir)
 void
 Editor::update_region_fade_visibility ()
 {
-	bool _fade_visibility = session->config.get_show_region_fades ();
+	bool _fade_visibility = _session->config.get_show_region_fades ();
 
 	for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 		AudioTimeAxisView* v = dynamic_cast<AudioTimeAxisView*>(*i);
@@ -5381,7 +5381,7 @@ Editor::update_region_fade_visibility ()
 void
 Editor::update_xfade_visibility ()
 {
-	_xfade_visibility = session->config.get_xfades_visible ();
+	_xfade_visibility = _session->config.get_xfades_visible ();
 
 	for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
 		AudioTimeAxisView* v = dynamic_cast<AudioTimeAxisView*>(*i);
@@ -5426,7 +5426,7 @@ void
 Editor::set_playhead_cursor ()
 {
 	if (entered_marker) {
-		session->request_locate (entered_marker->position(), session->transport_rolling());
+		_session->request_locate (entered_marker->position(), _session->transport_rolling());
 	} else {
 		nframes64_t where;
 		bool ignored;
@@ -5437,8 +5437,8 @@ Editor::set_playhead_cursor ()
 
 		snap_to (where);
 
-		if (session) {
-			session->request_locate (where, session->transport_rolling());
+		if (_session) {
+			_session->request_locate (where, _session->transport_rolling());
 		}
 	}
 }
@@ -5580,7 +5580,7 @@ Editor::ensure_track_visible(TimeAxisView *track)
 void
 Editor::set_loop_from_selection (bool play)
 {
-	if (session == 0 || selection->time.empty()) {
+	if (_session == 0 || selection->time.empty()) {
 		return;
 	}
 
@@ -5590,15 +5590,15 @@ Editor::set_loop_from_selection (bool play)
 	set_loop_range (start, end,  _("set loop range from selection"));
 
 	if (play) {
-		session->request_play_loop (true);
-		session->request_locate (start, true);
+		_session->request_play_loop (true);
+		_session->request_locate (start, true);
 	}
 }
 
 void
 Editor::set_loop_from_edit_range (bool play)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -5612,8 +5612,8 @@ Editor::set_loop_from_edit_range (bool play)
 	set_loop_range (start, end,  _("set loop range from edit range"));
 
 	if (play) {
-		session->request_play_loop (true);
-		session->request_locate (start, true);
+		_session->request_play_loop (true);
+		_session->request_locate (start, true);
 	}
 }
 
@@ -5643,15 +5643,15 @@ Editor::set_loop_from_region (bool play)
 	set_loop_range (start, end, _("set loop range from region"));
 
 	if (play) {
-		session->request_play_loop (true);
-		session->request_locate (start, true);
+		_session->request_play_loop (true);
+		_session->request_locate (start, true);
 	}
 }
 
 void
 Editor::set_punch_from_selection ()
 {
-	if (session == 0 || selection->time.empty()) {
+	if (_session == 0 || selection->time.empty()) {
 		return;
 	}
 
@@ -5664,7 +5664,7 @@ Editor::set_punch_from_selection ()
 void
 Editor::set_punch_from_edit_range ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -5721,7 +5721,7 @@ Editor::pitch_shift_regions ()
 void
 Editor::use_region_as_bar ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -5752,7 +5752,7 @@ Editor::define_one_bar (nframes64_t start, nframes64_t end)
 {
 	nframes64_t length = end - start;
 
-	const Meter& m (session->tempo_map().meter_at (start));
+	const Meter& m (_session->tempo_map().meter_at (start));
 
 	/* length = 1 bar */
 
@@ -5764,7 +5764,7 @@ Editor::define_one_bar (nframes64_t start, nframes64_t end)
 
 	/* beats per minute = */
 
-	double beats_per_minute = (session->frame_rate() * 60.0) / frames_per_beat;
+	double beats_per_minute = (_session->frame_rate() * 60.0) / frames_per_beat;
 
 	/* now decide whether to:
 
@@ -5773,11 +5773,11 @@ Editor::define_one_bar (nframes64_t start, nframes64_t end)
 
 	*/
 
-	const TempoSection& t (session->tempo_map().tempo_section_at (start));
+	const TempoSection& t (_session->tempo_map().tempo_section_at (start));
 
 	bool do_global = false;
 
-	if ((session->tempo_map().n_tempos() == 1) && (session->tempo_map().n_meters() == 1)) {
+	if ((_session->tempo_map().n_tempos() == 1) && (_session->tempo_map().n_meters() == 1)) {
 
 		/* only 1 tempo & 1 meter: ask if the user wants to set the tempo
 		   at the start, or create a new marker
@@ -5812,19 +5812,19 @@ Editor::define_one_bar (nframes64_t start, nframes64_t end)
 	}
 
 	begin_reversible_command (_("set tempo from region"));
-	XMLNode& before (session->tempo_map().get_state());
+	XMLNode& before (_session->tempo_map().get_state());
 
 	if (do_global) {
-		session->tempo_map().change_initial_tempo (beats_per_minute, t.note_type());
+		_session->tempo_map().change_initial_tempo (beats_per_minute, t.note_type());
 	} else if (t.frame() == start) {
-		session->tempo_map().change_existing_tempo_at (start, beats_per_minute, t.note_type());
+		_session->tempo_map().change_existing_tempo_at (start, beats_per_minute, t.note_type());
 	} else {
-		session->tempo_map().add_tempo (Tempo (beats_per_minute, t.note_type()), start);
+		_session->tempo_map().add_tempo (Tempo (beats_per_minute, t.note_type()), start);
 	}
 
-	XMLNode& after (session->tempo_map().get_state());
+	XMLNode& after (_session->tempo_map().get_state());
 
-	session->add_command (new MementoCommand<TempoMap>(session->tempo_map(), &before, &after));
+	_session->add_command (new MementoCommand<TempoMap>(_session->tempo_map(), &before, &after));
 	commit_reversible_command ();
 }
 
@@ -5833,7 +5833,7 @@ Editor::split_region_at_transients ()
 {
 	AnalysisFeatureList positions;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -5845,7 +5845,7 @@ Editor::split_region_at_transients ()
 		return;
 	}
 
-	session->begin_reversible_command (_("split regions"));
+	_session->begin_reversible_command (_("split regions"));
 
 	for (RegionSelection::iterator i = rs.begin(); i != rs.end(); ) {
 
@@ -5864,7 +5864,7 @@ Editor::split_region_at_transients ()
 		i = tmp;
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 
 }
 
@@ -5963,7 +5963,7 @@ Editor::split_region_at_points (boost::shared_ptr<Region> r, AnalysisFeatureList
 
 		string new_name;
 
-		if (session->region_name (new_name, r->name())) {
+		if (_session->region_name (new_name, r->name())) {
 			break;
 		}
 
@@ -5993,7 +5993,7 @@ Editor::split_region_at_points (boost::shared_ptr<Region> r, AnalysisFeatureList
 
 	XMLNode& after (pl->get_state());
 
-	session->add_command (new MementoCommand<Playlist>(*pl, &before, &after));
+	_session->add_command (new MementoCommand<Playlist>(*pl, &before, &after));
 }
 
 void
@@ -6001,11 +6001,11 @@ Editor::tab_to_transient (bool forward)
 {
 	AnalysisFeatureList positions;
 
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
-	nframes64_t pos = session->audible_frame ();
+	nframes64_t pos = _session->audible_frame ();
 
 	if (!selection->tracks.empty()) {
 
@@ -6043,7 +6043,7 @@ Editor::tab_to_transient (bool forward)
 		}
 	}
 
-	TransientDetector::cleanup_transients (positions, session->frame_rate(), 3.0);
+	TransientDetector::cleanup_transients (positions, _session->frame_rate(), 3.0);
 
 	if (forward) {
 		AnalysisFeatureList::iterator x;
@@ -6055,7 +6055,7 @@ Editor::tab_to_transient (bool forward)
 		}
 
 		if (x != positions.end ()) {
-			session->request_locate (*x);
+			_session->request_locate (*x);
 		}
 
 	} else {
@@ -6068,19 +6068,19 @@ Editor::tab_to_transient (bool forward)
 		}
 
 		if (x != positions.rend ()) {
-			session->request_locate (*x);
+			_session->request_locate (*x);
 		}
 	}
 }
 void
 Editor::playhead_forward_to_grid ()
 {
-	if (!session) return;
+	if (!_session) return;
 	nframes64_t pos = playhead_cursor->current_frame;
 	if (pos < max_frames - 1) {
 		pos += 2;
 		snap_to_internal (pos, 1, false);
-		session->request_locate (pos);
+		_session->request_locate (pos);
 	}
 }
 
@@ -6088,12 +6088,12 @@ Editor::playhead_forward_to_grid ()
 void
 Editor::playhead_backward_to_grid ()
 {
-	if (!session) return;
+	if (!_session) return;
 	nframes64_t pos = playhead_cursor->current_frame;
 	if (pos > 2) {
 		pos -= 2;
 		snap_to_internal (pos, -1, false);
-		session->request_locate (pos);
+		_session->request_locate (pos);
 	}
 }
 
@@ -6207,7 +6207,7 @@ Editor::remove_tracks ()
 	}
 
 	for (vector<boost::shared_ptr<Route> >::iterator x = routes.begin(); x != routes.end(); ++x) {
-		session->remove_route (*x);
+		_session->remove_route (*x);
 	}
 }
 
@@ -6233,7 +6233,7 @@ Editor::do_insert_time ()
 	table.attach (time_label, 0, 1, 0, 1, FILL | EXPAND);
 	AudioClock clock ("insertTimeClock", true, X_("InsertTimeClock"), true, false, true, true);
 	clock.set (0);
-	clock.set_session (session);
+	clock.set_session (_session);
 	clock.set_bbt_reference (pos);
 	table.attach (clock, 1, 2, 0, 1);
 
@@ -6317,7 +6317,7 @@ Editor::insert_time (nframes64_t pos, nframes64_t frames, InsertTimeOption opt,
 
 			XMLNode &after = pl->get_state();
 
-			session->add_command (new MementoCommand<Playlist> (*pl, &before, &after));
+			_session->add_command (new MementoCommand<Playlist> (*pl, &before, &after));
 			commit = true;
 		}
 
@@ -6332,8 +6332,8 @@ Editor::insert_time (nframes64_t pos, nframes64_t frames, InsertTimeOption opt,
 	/* markers */
 	if (markers_too) {
 		bool moved = false;
-		XMLNode& before (session->locations()->get_state());
-		Locations::LocationList copy (session->locations()->list());
+		XMLNode& before (_session->locations()->get_state());
+		Locations::LocationList copy (_session->locations()->list());
 
 		for (Locations::LocationList::iterator i = copy.begin(); i != copy.end(); ++i) {
 
@@ -6349,13 +6349,13 @@ Editor::insert_time (nframes64_t pos, nframes64_t frames, InsertTimeOption opt,
 		}
 
 		if (moved) {
-			XMLNode& after (session->locations()->get_state());
-			session->add_command (new MementoCommand<Locations>(*session->locations(), &before, &after));
+			XMLNode& after (_session->locations()->get_state());
+			_session->add_command (new MementoCommand<Locations>(*_session->locations(), &before, &after));
 		}
 	}
 
 	if (tempo_too) {
-		session->tempo_map().insert_time (pos, frames);
+		_session->tempo_map().insert_time (pos, frames);
 	}
 
 	if (commit) {
diff --git a/gtk2_ardour/editor_regions.cc b/gtk2_ardour/editor_regions.cc
index 8aa6d94192..2501f93726 100644
--- a/gtk2_ardour/editor_regions.cc
+++ b/gtk2_ardour/editor_regions.cc
@@ -130,13 +130,15 @@ EditorRegions::EditorRegions (Editor* e)
 }
 
 void
-EditorRegions::connect_to_session (ARDOUR::Session* s)
+EditorRegions::set_session (ARDOUR::Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
-	_session_connections.push_back (_session->RegionsAdded.connect (sigc::mem_fun(*this, &EditorRegions::handle_new_regions)));
-	_session_connections.push_back (_session->RegionRemoved.connect (sigc::mem_fun(*this, &EditorRegions::handle_region_removed)));
-	_session_connections.push_back (_session->RegionHiddenChange.connect (sigc::mem_fun(*this, &EditorRegions::region_hidden)));
+	if (_session) {
+		_session_connections.add_connection (_session->RegionsAdded.connect (boost::bind (&EditorRegions::handle_new_regions, this, _1)));
+		_session_connections.add_connection (_session->RegionRemoved.connect (boost::bind (&EditorRegions::handle_region_removed, this, _1)));
+		_session_connections.add_connection (_session->RegionHiddenChange.connect (boost::bind (&EditorRegions::region_hidden, this, _1)));
+	}
 
 	redisplay ();
 }
diff --git a/gtk2_ardour/editor_regions.h b/gtk2_ardour/editor_regions.h
index cc031b141e..59659d3879 100644
--- a/gtk2_ardour/editor_regions.h
+++ b/gtk2_ardour/editor_regions.h
@@ -26,7 +26,7 @@ class EditorRegions : public EditorComponent
 public:
 	EditorRegions (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	Gtk::Widget& widget () {
 		return _scroller;
diff --git a/gtk2_ardour/editor_route_groups.cc b/gtk2_ardour/editor_route_groups.cc
index 10edec8682..d0d0298c08 100644
--- a/gtk2_ardour/editor_route_groups.cc
+++ b/gtk2_ardour/editor_route_groups.cc
@@ -604,7 +604,9 @@ EditorRouteGroups::groups_changed ()
 		row[_columns.routegroup] = 0;
 	}
 
-	_session->foreach_route_group (sigc::mem_fun (*this, &EditorRouteGroups::add));
+	if (_session) {
+		_session->foreach_route_group (sigc::mem_fun (*this, &EditorRouteGroups::add));
+	}
 }
 
 void
@@ -661,12 +663,14 @@ EditorRouteGroups::clear ()
 }
 
 void
-EditorRouteGroups::connect_to_session (Session* s)
+EditorRouteGroups::set_session (Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
-	_session_connections.push_back (_session->route_group_added.connect (sigc::mem_fun (*this, &EditorRouteGroups::add)));
-	_session_connections.push_back (_session->route_group_removed.connect (sigc::mem_fun (*this, &EditorRouteGroups::groups_changed)));
+	if (_session) {
+		_session_connections.add_connection (_session->route_group_added.connect (boost::bind (&EditorRouteGroups::add, this, _1)));
+		_session_connections.add_connection (_session->route_group_removed.connect (boost::bind (&EditorRouteGroups::groups_changed, this)));
+	}
 
 	groups_changed ();
 }
diff --git a/gtk2_ardour/editor_route_groups.h b/gtk2_ardour/editor_route_groups.h
index b1b82fb531..5408649f95 100644
--- a/gtk2_ardour/editor_route_groups.h
+++ b/gtk2_ardour/editor_route_groups.h
@@ -24,7 +24,7 @@ class EditorRouteGroups : public EditorComponent
 public:
 	EditorRouteGroups (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	Gtk::Widget& widget () {
 		return *_display_packer;
diff --git a/gtk2_ardour/editor_routes.cc b/gtk2_ardour/editor_routes.cc
index de6b081fd4..e3a831a8b9 100644
--- a/gtk2_ardour/editor_routes.cc
+++ b/gtk2_ardour/editor_routes.cc
@@ -150,17 +150,19 @@ EditorRoutes::EditorRoutes (Editor* e)
 	_model->signal_rows_reordered().connect (sigc::mem_fun (*this, &EditorRoutes::reordered));
 	_display.signal_button_press_event().connect (sigc::mem_fun (*this, &EditorRoutes::button_press), false);
 
-	Route::SyncOrderKeys.connect (sigc::mem_fun (*this, &EditorRoutes::sync_order_keys));
+	scoped_connect (Route::SyncOrderKeys, (sigc::mem_fun (*this, &EditorRoutes::sync_order_keys)));
 }
 
 void
-EditorRoutes::connect_to_session (Session* s)
+EditorRoutes::set_session (Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
 	initial_display ();
 
-	_session->SoloChanged.connect (sigc::mem_fun (*this, &EditorRoutes::solo_changed_so_update_mute));
+	if (_session) {
+		scoped_connect (_session->SoloChanged, (sigc::mem_fun (*this, &EditorRoutes::solo_changed_so_update_mute)));
+	}
 }
 
 void
@@ -260,15 +262,15 @@ EditorRoutes::show_menu ()
 void
 EditorRoutes::redisplay ()
 {
+	if (_no_redisplay || !_session) {
+		return;
+	}
+
 	TreeModel::Children rows = _model->children();
 	TreeModel::Children::iterator i;
 	uint32_t position;
 	int n;
 
-	if (_no_redisplay) {
-		return;
-	}
-
 	for (n = 0, position = 0, i = rows.begin(); i != rows.end(); ++i) {
 		TimeAxisView *tv = (*i)[_columns.tv];
 		boost::shared_ptr<Route> route = (*i)[_columns.route];
@@ -380,18 +382,19 @@ EditorRoutes::routes_added (list<RouteTimeAxisView*> routes)
 		_ignore_reorder = false;
 
 		boost::weak_ptr<Route> wr ((*x)->route());
-		(*x)->route()->gui_changed.connect (sigc::mem_fun (*this, &EditorRoutes::handle_gui_changes));
-		(*x)->route()->NameChanged.connect (sigc::bind (sigc::mem_fun (*this, &EditorRoutes::route_name_changed), wr));
-		(*x)->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &EditorRoutes::route_removed), *x));
+
+		scoped_connect ((*x)->route()->gui_changed, boost::bind (&EditorRoutes::handle_gui_changes, this, _1, _2));
+		scoped_connect ((*x)->route()->NameChanged, boost::bind (&EditorRoutes::route_name_changed, this, wr));
+		scoped_connect ((*x)->GoingAway, boost::bind (&EditorRoutes::route_removed, this, *x));
 
 		if ((*x)->is_track()) {
 			boost::shared_ptr<Track> t = boost::dynamic_pointer_cast<Track> ((*x)->route());
-			t->diskstream()->RecordEnableChanged.connect (sigc::mem_fun (*this, &EditorRoutes::update_rec_display));
+			scoped_connect (t->diskstream()->RecordEnableChanged, boost::bind (&EditorRoutes::update_rec_display, this));
 		}
 
-		(*x)->route()->mute_changed.connect (sigc::mem_fun (*this, &EditorRoutes::update_mute_display));
-		(*x)->route()->solo_changed.connect (sigc::mem_fun (*this, &EditorRoutes::update_solo_display));
-		(*x)->route()->solo_isolated_changed.connect (sigc::mem_fun (*this, &EditorRoutes::update_solo_isolate_display));
+		scoped_connect ((*x)->route()->mute_changed, boost::bind (&EditorRoutes::update_mute_display, this));
+		scoped_connect ((*x)->route()->solo_changed, boost::bind (&EditorRoutes::update_solo_display, this));
+		scoped_connect ((*x)->route()->solo_isolated_changed, boost::bind (&EditorRoutes::update_solo_isolate_display, this));
 	}
 
 	update_rec_display ();
@@ -710,15 +713,19 @@ struct EditorOrderRouteSorter {
 void
 EditorRoutes::initial_display ()
 {
+	suspend_redisplay ();
+	_model->clear ();
+
+	if (!_session) {
+		resume_redisplay ();
+		return;
+	}
+
 	boost::shared_ptr<RouteList> routes = _session->get_routes();
 	RouteList r (*routes);
 	EditorOrderRouteSorter sorter;
 
 	r.sort (sorter);
-
-	suspend_redisplay ();
-
-	_model->clear ();
 	_editor->handle_new_route (r);
 
 	/* don't show master bus in a new session */
@@ -900,19 +907,19 @@ EditorRoutes::update_rec_display ()
 }
 
 void
-EditorRoutes::update_mute_display (void* /*src*/)
+EditorRoutes::update_mute_display ()
 {
 	TreeModel::Children rows = _model->children();
 	TreeModel::Children::iterator i;
 
 	for (i = rows.begin(); i != rows.end(); ++i) {
 		boost::shared_ptr<Route> route = (*i)[_columns.route];
-		(*i)[_columns.mute_state] = RouteUI::mute_visual_state (*_session, route) > 0 ? 1 : 0;
+		(*i)[_columns.mute_state] = RouteUI::mute_visual_state (_session, route) > 0 ? 1 : 0;
 	}
 }
 
 void
-EditorRoutes::update_solo_display (void* /*src*/)
+EditorRoutes::update_solo_display ()
 {
 	TreeModel::Children rows = _model->children();
 	TreeModel::Children::iterator i;
@@ -924,7 +931,7 @@ EditorRoutes::update_solo_display (void* /*src*/)
 }
 
 void
-EditorRoutes::update_solo_isolate_display (void* /*src*/)
+EditorRoutes::update_solo_isolate_display ()
 {
 	TreeModel::Children rows = _model->children();
 	TreeModel::Children::iterator i;
@@ -973,8 +980,7 @@ void
 EditorRoutes::solo_changed_so_update_mute ()
 {
 	ENSURE_GUI_THREAD (*this, &EditorRoutes::solo_changed_so_update_mute)
-
-	update_mute_display (this);
+	update_mute_display ();
 }
 
 void
diff --git a/gtk2_ardour/editor_routes.h b/gtk2_ardour/editor_routes.h
index 756796dbda..23e1e93388 100644
--- a/gtk2_ardour/editor_routes.h
+++ b/gtk2_ardour/editor_routes.h
@@ -17,12 +17,18 @@
 
 */
 
-class EditorRoutes : public EditorComponent
+#ifndef __ardour_gtk_editor_route_h__
+#define __ardour_gtk_editor_route_h__
+
+#include "pbd/scoped_connections.h"
+#include "editor_component.h"
+
+class EditorRoutes : public EditorComponent, public PBD::ScopedConnectionList
 {
 public:
 	EditorRoutes (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	Gtk::Widget& widget () {
 		return _scroller;
@@ -66,9 +72,9 @@ private:
 	void route_removed (TimeAxisView *);
 	void handle_gui_changes (std::string const &, void *);
 	void update_rec_display ();
-	void update_mute_display (void* /*src*/);
-	void update_solo_display (void* /*src*/);
-	void update_solo_isolate_display (void* /*src*/);
+	void update_mute_display ();
+	void update_solo_display ();
+	void update_solo_isolate_display ();
 	void set_all_tracks_visibility (bool);
 	void set_all_audio_visibility (int, bool);
 	void show_all_routes ();
@@ -126,3 +132,5 @@ private:
 	
 	Gtk::Menu* _menu;
 };
+
+#endif /* __ardour_gtk_editor_route_h__ */
diff --git a/gtk2_ardour/editor_rulers.cc b/gtk2_ardour/editor_rulers.cc
index be806eb366..880b6812b5 100644
--- a/gtk2_ardour/editor_rulers.cc
+++ b/gtk2_ardour/editor_rulers.cc
@@ -215,7 +215,7 @@ Editor::ruler_scroll (GdkEventScroll* event)
 gint
 Editor::ruler_button_press (GdkEventButton* ev)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return FALSE;
 	}
 
@@ -241,8 +241,8 @@ Editor::ruler_button_press (GdkEventButton* ev)
 	if (ev->button == 1) {
 		// Since we will locate the playhead on button release, cancel any running
 		// auditions.
-		if (session->is_auditioning()) {
-			session->cancel_audition ();
+		if (_session->is_auditioning()) {
+			_session->cancel_audition ();
 		}
 
 		/* playhead cursor */
@@ -258,7 +258,7 @@ Editor::ruler_button_press (GdkEventButton* ev)
 gint
 Editor::ruler_button_release (GdkEventButton* ev)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return FALSE;
 	}
 
@@ -308,7 +308,7 @@ Editor::ruler_label_button_release (GdkEventButton* ev)
 gint
 Editor::ruler_mouse_motion (GdkEventMotion* ev)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return FALSE;
 	}
 
@@ -443,15 +443,15 @@ Editor::store_ruler_visibility ()
 	node->add_property (X_("transportmarker"), ruler_loop_punch_action->get_active() ? "yes": "no");
 	node->add_property (X_("cdmarker"), ruler_cd_marker_action->get_active() ? "yes": "no");
 
-	session->add_extra_xml (*node);
-	session->set_dirty ();
+	_session->add_extra_xml (*node);
+	_session->set_dirty ();
 }
 
 void
 Editor::restore_ruler_visibility ()
 {
 	XMLProperty* prop;
-	XMLNode * node = session->extra_xml (X_("RulerVisibility"));
+	XMLNode * node = _session->extra_xml (X_("RulerVisibility"));
 
 	no_ruler_shown_update = true;
 
@@ -529,11 +529,11 @@ Editor::restore_ruler_visibility ()
 			}
 
 		} else {
-			// this session doesn't yet know about the cdmarker ruler
+			// this _session doesn't yet know about the cdmarker ruler
 			// as a benefit to the user who doesn't know the feature exists, show the ruler if
 			// any cd marks exist
 			ruler_cd_marker_action->set_active (false);
-			const Locations::LocationList & locs = session->locations()->list();
+			const Locations::LocationList & locs = _session->locations()->list();
 			for (Locations::LocationList::const_iterator i = locs.begin(); i != locs.end(); ++i) {
 				if ((*i)->is_cd_marker()) {
 					ruler_cd_marker_action->set_active (true);
@@ -774,7 +774,7 @@ Editor::update_just_timecode ()
 {
 	ENSURE_GUI_THREAD (*this, &Editor::update_just_timecode)
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -782,14 +782,14 @@ Editor::update_just_timecode ()
 
 	if (ruler_timecode_action->get_active()) {
 		gtk_custom_ruler_set_range (GTK_CUSTOM_RULER(_timecode_ruler), leftmost_frame, rightmost_frame,
-					    leftmost_frame, session->current_end_frame());
+					    leftmost_frame, _session->current_end_frame());
 	}
 }
 
 void
 Editor::compute_fixed_ruler_scale ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -807,7 +807,7 @@ Editor::update_fixed_rulers ()
 {
 	nframes64_t rightmost_frame;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -823,24 +823,24 @@ Editor::update_fixed_rulers ()
 
 	if (ruler_timecode_action->get_active()) {
 		gtk_custom_ruler_set_range (GTK_CUSTOM_RULER(_timecode_ruler), leftmost_frame, rightmost_frame,
-					    leftmost_frame, session->current_end_frame());
+					    leftmost_frame, _session->current_end_frame());
 	}
 
 	if (ruler_samples_action->get_active()) {
 		gtk_custom_ruler_set_range (GTK_CUSTOM_RULER(_frames_ruler), leftmost_frame, rightmost_frame,
-					    leftmost_frame, session->current_end_frame());
+					    leftmost_frame, _session->current_end_frame());
 	}
 
 	if (ruler_minsec_action->get_active()) {
 		gtk_custom_ruler_set_range (GTK_CUSTOM_RULER(_minsec_ruler), leftmost_frame, rightmost_frame,
-					    leftmost_frame, session->current_end_frame());
+					    leftmost_frame, _session->current_end_frame());
 	}
 }
 
 void
 Editor::update_tempo_based_rulers ()
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
@@ -848,7 +848,7 @@ Editor::update_tempo_based_rulers ()
 
 	if (ruler_bbt_action->get_active()) {
 		gtk_custom_ruler_set_range (GTK_CUSTOM_RULER(_bbt_ruler), leftmost_frame, leftmost_frame+current_page_frames(),
-					    leftmost_frame, session->current_end_frame());
+					    leftmost_frame, _session->current_end_frame());
 	}
 }
 
@@ -885,11 +885,11 @@ Editor::set_timecode_ruler_scale (gdouble lower, gdouble upper)
 	nframes64_t spacer;
 	nframes64_t fr;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	fr = session->frame_rate();
+	fr = _session->frame_rate();
 
 	if (lower > (spacer = (nframes64_t)(128 * Editor::get_current_zoom ()))) {
 		lower = lower - spacer;
@@ -899,26 +899,26 @@ Editor::set_timecode_ruler_scale (gdouble lower, gdouble upper)
 	upper = upper + spacer;
 	range = (nframes64_t) floor (upper - lower);
 
-	if (range < (2 * session->frames_per_timecode_frame())) { /* 0 - 2 frames */
+	if (range < (2 * _session->frames_per_timecode_frame())) { /* 0 - 2 frames */
 		timecode_ruler_scale = timecode_show_bits;
 		timecode_mark_modulo = 20;
-		timecode_nmarks = 2 + (2 * session->config.get_subframes_per_frame());
+		timecode_nmarks = 2 + (2 * _session->config.get_subframes_per_frame());
 	} else if (range <= (fr / 4)) { /* 2 frames - 0.250 second */
 		timecode_ruler_scale = timecode_show_frames;
 		timecode_mark_modulo = 1;
-		timecode_nmarks = 2 + (range / (nframes64_t)session->frames_per_timecode_frame());
+		timecode_nmarks = 2 + (range / (nframes64_t)_session->frames_per_timecode_frame());
 	} else if (range <= (fr / 2)) { /* 0.25-0.5 second */
 		timecode_ruler_scale = timecode_show_frames;
 		timecode_mark_modulo = 2;
-		timecode_nmarks = 2 + (range / (nframes64_t)session->frames_per_timecode_frame());
+		timecode_nmarks = 2 + (range / (nframes64_t)_session->frames_per_timecode_frame());
 	} else if (range <= fr) { /* 0.5-1 second */
 		timecode_ruler_scale = timecode_show_frames;
 		timecode_mark_modulo = 5;
-		timecode_nmarks = 2 + (range / (nframes64_t)session->frames_per_timecode_frame());
+		timecode_nmarks = 2 + (range / (nframes64_t)_session->frames_per_timecode_frame());
 	} else if (range <= 2 * fr) { /* 1-2 seconds */
 		timecode_ruler_scale = timecode_show_frames;
 		timecode_mark_modulo = 10;
-		timecode_nmarks = 2 + (range / (nframes64_t)session->frames_per_timecode_frame());
+		timecode_nmarks = 2 + (range / (nframes64_t)_session->frames_per_timecode_frame());
 	} else if (range <= 8 * fr) { /* 2-8 seconds */
 		timecode_ruler_scale = timecode_show_seconds;
 		timecode_mark_modulo = 1;
@@ -987,7 +987,7 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 	gchar buf[16];
 	gint n;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return 0;
 	}
 
@@ -1004,10 +1004,10 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 	case timecode_show_bits:
 
 		// Find timecode time of this sample (pos) with subframe accuracy
-		session->sample_to_timecode(pos, timecode, true /* use_offset */, true /* use_subframes */ );
+		_session->sample_to_timecode(pos, timecode, true /* use_offset */, true /* use_subframes */ );
 
 		for (n = 0; n < timecode_nmarks; n++) {
-			session->timecode_to_sample(timecode, pos, true /* use_offset */, true /* use_subframes */ );
+			_session->timecode_to_sample(timecode, pos, true /* use_offset */, true /* use_subframes */ );
 			if ((timecode.subframes % timecode_mark_modulo) == 0) {
 				if (timecode.subframes == 0) {
 					(*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1025,17 +1025,17 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 			(*marks)[n].position = pos;
 
 			// Increment subframes by one
-			Timecode::increment_subframes( timecode, session->config.get_subframes_per_frame() );
+			Timecode::increment_subframes( timecode, _session->config.get_subframes_per_frame() );
 		}
 	  break;
 	case timecode_show_seconds:
 		// Find timecode time of this sample (pos)
-		session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
 		// Go to next whole second down
 		Timecode::seconds_floor( timecode );
 
 		for (n = 0; n < timecode_nmarks; n++) {
-			session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
+			_session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
 			if ((timecode.seconds % timecode_mark_modulo) == 0) {
 				if (timecode.seconds == 0) {
 					(*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1052,17 +1052,17 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 
 			}
 			(*marks)[n].label = g_strdup (buf);
-			Timecode::increment_seconds( timecode, session->config.get_subframes_per_frame() );
+			Timecode::increment_seconds( timecode, _session->config.get_subframes_per_frame() );
 		}
 	  break;
 	case timecode_show_minutes:
 		// Find timecode time of this sample (pos)
-		session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
 		// Go to next whole minute down
 		Timecode::minutes_floor( timecode );
 
 		for (n = 0; n < timecode_nmarks; n++) {
-			session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
+			_session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
 			if ((timecode.minutes % timecode_mark_modulo) == 0) {
 				if (timecode.minutes == 0) {
 					(*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1077,18 +1077,18 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 			}
 			(*marks)[n].label = g_strdup (buf);
 			(*marks)[n].position = pos;
-			Timecode::increment_minutes( timecode, session->config.get_subframes_per_frame() );
+			Timecode::increment_minutes( timecode, _session->config.get_subframes_per_frame() );
 		}
 
 	  break;
 	case timecode_show_hours:
 		// Find timecode time of this sample (pos)
-		session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
 		// Go to next whole hour down
 		Timecode::hours_floor( timecode );
 
 		for (n = 0; n < timecode_nmarks; n++) {
-			session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
+			_session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
 			if ((timecode.hours % timecode_mark_modulo) == 0) {
 				(*marks)[n].style = GtkCustomRulerMarkMajor;
 				snprintf (buf, sizeof(buf), "%s%02u:%02u:%02u:%02u", timecode.negative ? "-" : "", timecode.hours, timecode.minutes, timecode.seconds, timecode.frames);
@@ -1100,17 +1100,17 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 			(*marks)[n].label = g_strdup (buf);
 			(*marks)[n].position = pos;
 
-			Timecode::increment_hours( timecode, session->config.get_subframes_per_frame() );
+			Timecode::increment_hours( timecode, _session->config.get_subframes_per_frame() );
 		}
 	  break;
 	case timecode_show_frames:
 		// Find timecode time of this sample (pos)
-		session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
+		_session->sample_to_timecode(pos, timecode, true /* use_offset */, false /* use_subframes */ );
 		// Go to next whole frame down
 		Timecode::frames_floor( timecode );
 
 		for (n = 0; n < timecode_nmarks; n++) {
-			session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
+			_session->timecode_to_sample(timecode, pos, true /* use_offset */, false /* use_subframes */ );
 			if ((timecode.frames % timecode_mark_modulo) == 0)  {
 				if (timecode.frames == 0) {
 				  (*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1126,7 +1126,7 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 
 			}
 			(*marks)[n].label = g_strdup (buf);
-			Timecode::increment( timecode, session->config.get_subframes_per_frame() );
+			Timecode::increment( timecode, _session->config.get_subframes_per_frame() );
 		}
 
 	  break;
@@ -1139,14 +1139,14 @@ Editor::metric_get_timecode (GtkCustomRulerMark **marks, gdouble lower, gdouble
 void
 Editor::compute_bbt_ruler_scale (nframes64_t lower, nframes64_t upper)
 {
-        if (session == 0) {
+        if (_session == 0) {
                 return;
         }
 	TempoMap::BBTPointList::iterator i;
         BBT_Time lower_beat, upper_beat; // the beats at each end of the ruler
 
-        session->bbt_time((jack_nframes_t) lower, lower_beat);
-        session->bbt_time((jack_nframes_t) upper, upper_beat);
+        _session->bbt_time((jack_nframes_t) lower, lower_beat);
+        _session->bbt_time((jack_nframes_t) upper, upper_beat);
         uint32_t beats = 0;
 
 	bbt_accent_modulo = 1;
@@ -1224,7 +1224,7 @@ Editor::compute_bbt_ruler_scale (nframes64_t lower, nframes64_t upper)
 gint
 Editor::metric_get_bbt (GtkCustomRulerMark **marks, gdouble lower, gdouble /*upper*/, gint /*maxchars*/)
 {
-        if (session == 0) {
+        if (_session == 0) {
                 return 0;
         }
 
@@ -1341,9 +1341,9 @@ Editor::metric_get_bbt (GtkCustomRulerMark **marks, gdouble lower, gdouble /*upp
 				  next_beat.beats = 1;
 			}
 
-			next_beat_pos = session->tempo_map().frame_time(next_beat);
+			next_beat_pos = _session->tempo_map().frame_time(next_beat);
 
-			frame_skip = (nframes64_t) floor (frame_skip_error = (session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
+			frame_skip = (nframes64_t) floor (frame_skip_error = (_session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
 			frame_skip_error -= frame_skip;
 			skip = (uint32_t) (Meter::ticks_per_beat / bbt_beat_subdivision);
 
@@ -1433,9 +1433,9 @@ Editor::metric_get_bbt (GtkCustomRulerMark **marks, gdouble lower, gdouble /*upp
 				  next_beat.beats = 1;
 			}
 
-			next_beat_pos = session->tempo_map().frame_time(next_beat);
+			next_beat_pos = _session->tempo_map().frame_time(next_beat);
 
-			frame_skip = (nframes64_t) floor (frame_skip_error = (session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
+			frame_skip = (nframes64_t) floor (frame_skip_error = (_session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
 			frame_skip_error -= frame_skip;
 			skip = (uint32_t) (Meter::ticks_per_beat / bbt_beat_subdivision);
 
@@ -1530,9 +1530,9 @@ Editor::metric_get_bbt (GtkCustomRulerMark **marks, gdouble lower, gdouble /*upp
 				  next_beat.beats = 1;
 			}
 
-			next_beat_pos = session->tempo_map().frame_time(next_beat);
+			next_beat_pos = _session->tempo_map().frame_time(next_beat);
 
-			frame_skip = (nframes64_t) floor (frame_skip_error = (session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
+			frame_skip = (nframes64_t) floor (frame_skip_error = (_session->frame_rate() *  60) / (bbt_beat_subdivision * (*i).tempo->beats_per_minute()));
 			frame_skip_error -= frame_skip;
 			skip = (uint32_t) (Meter::ticks_per_beat / bbt_beat_subdivision);
 
@@ -1704,15 +1704,15 @@ Editor::metric_get_frames (GtkCustomRulerMark **marks, gdouble lower, gdouble up
 	gint nmarks;
 	gint n;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return 0;
 	}
 
 	mark_interval = (iupper - ilower) / 5;
-	if (mark_interval > session->frame_rate()) {
-		mark_interval -= mark_interval % session->frame_rate();
+	if (mark_interval > _session->frame_rate()) {
+		mark_interval -= mark_interval % _session->frame_rate();
 	} else {
-		mark_interval = session->frame_rate() / (session->frame_rate() / mark_interval ) ;
+		mark_interval = _session->frame_rate() / (_session->frame_rate() / mark_interval ) ;
 	}
 	nmarks = 5;
 	*marks = (GtkCustomRulerMark *) g_malloc (sizeof(GtkCustomRulerMark) * nmarks);
@@ -1765,11 +1765,11 @@ Editor::set_minsec_ruler_scale (gdouble lower, gdouble upper)
 	nframes64_t fr;
 	nframes64_t spacer;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	fr = session->frame_rate();
+	fr = _session->frame_rate();
 
 	/* to prevent 'flashing' */
 	if (lower > (spacer = (nframes64_t)(128 * Editor::get_current_zoom ()))) {
@@ -1866,7 +1866,7 @@ Editor::metric_get_minsec (GtkCustomRulerMark **marks, gdouble lower, gdouble /*
 	gchar buf[16];
 	gint n;
 
-	if (session == 0) {
+	if (_session == 0) {
 		return 0;
 	}
 
@@ -1882,7 +1882,7 @@ Editor::metric_get_minsec (GtkCustomRulerMark **marks, gdouble lower, gdouble /*
 	switch (minsec_ruler_scale) {
 	case minsec_show_seconds:
 		for (n = 0; n < minsec_nmarks; pos += minsec_mark_interval, ++n) {
-                	sample_to_clock_parts (pos, session->frame_rate(), &hrs, &mins, &secs, &millisecs);
+                	sample_to_clock_parts (pos, _session->frame_rate(), &hrs, &mins, &secs, &millisecs);
               	  	if (secs % minsec_mark_modulo == 0) {
 				if (secs == 0) {
 					(*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1900,7 +1900,7 @@ Editor::metric_get_minsec (GtkCustomRulerMark **marks, gdouble lower, gdouble /*
 	  break;
 	case minsec_show_minutes:
 		for (n = 0; n < minsec_nmarks; pos += minsec_mark_interval, ++n) {
-                        sample_to_clock_parts (pos, session->frame_rate(), &hrs, &mins, &secs, &millisecs);
+                        sample_to_clock_parts (pos, _session->frame_rate(), &hrs, &mins, &secs, &millisecs);
                         if (mins % minsec_mark_modulo == 0) {
                                 if (mins == 0) {
                                         (*marks)[n].style = GtkCustomRulerMarkMajor;
@@ -1918,7 +1918,7 @@ Editor::metric_get_minsec (GtkCustomRulerMark **marks, gdouble lower, gdouble /*
 	  break;
 	case minsec_show_hours:
 		 for (n = 0; n < minsec_nmarks; pos += minsec_mark_interval, ++n) {
-                        sample_to_clock_parts (pos, session->frame_rate(), &hrs, &mins, &secs, &millisecs);
+                        sample_to_clock_parts (pos, _session->frame_rate(), &hrs, &mins, &secs, &millisecs);
                         if (hrs % minsec_mark_modulo == 0) {
                                 (*marks)[n].style = GtkCustomRulerMarkMajor;
                                 snprintf (buf, sizeof(buf), "%02ld:%02ld:%02ld.%03ld", hrs, mins, secs, millisecs);
@@ -1932,7 +1932,7 @@ Editor::metric_get_minsec (GtkCustomRulerMark **marks, gdouble lower, gdouble /*
 	      break;
 	case minsec_show_frames:
 		for (n = 0; n < minsec_nmarks; pos += minsec_mark_interval, ++n) {
-			sample_to_clock_parts (pos, session->frame_rate(), &hrs, &mins, &secs, &millisecs);
+			sample_to_clock_parts (pos, _session->frame_rate(), &hrs, &mins, &secs, &millisecs);
 			if (millisecs % minsec_mark_modulo == 0) {
 				if (secs == 0) {
 					(*marks)[n].style = GtkCustomRulerMarkMajor;
diff --git a/gtk2_ardour/editor_selection.cc b/gtk2_ardour/editor_selection.cc
index 59c020feae..4e66847ba2 100644
--- a/gtk2_ardour/editor_selection.cc
+++ b/gtk2_ardour/editor_selection.cc
@@ -1037,7 +1037,7 @@ Editor::set_selection_from_punch()
 {
 	Location* location;
 
-	if ((location = session->locations()->auto_punch_location()) == 0)  {
+	if ((location = _session->locations()->auto_punch_location()) == 0)  {
 		return;
 	}
 
@@ -1049,7 +1049,7 @@ Editor::set_selection_from_loop()
 {
 	Location* location;
 
-	if ((location = session->locations()->auto_loop_location()) == 0)  {
+	if ((location = _session->locations()->auto_loop_location()) == 0)  {
 		return;
 	}
 	set_selection_from_range (*location);
@@ -1107,7 +1107,7 @@ Editor::select_all_selectables_using_time_selection ()
 void
 Editor::select_all_selectables_using_punch()
 {
-	Location* location = session->locations()->auto_punch_location();
+	Location* location = _session->locations()->auto_punch_location();
 	list<Selectable *> touched;
 
 	if (location == 0 || (location->end() - location->start() <= 1))  {
@@ -1138,7 +1138,7 @@ Editor::select_all_selectables_using_punch()
 void
 Editor::select_all_selectables_using_loop()
 {
-	Location* location = session->locations()->auto_loop_location();
+	Location* location = _session->locations()->auto_loop_location();
 	list<Selectable *> touched;
 
 	if (location == 0 || (location->end() - location->start() <= 1))  {
@@ -1176,7 +1176,7 @@ Editor::select_all_selectables_using_cursor (EditorCursor *cursor, bool after)
 	if (after) {
 		begin_reversible_command (_("select all after cursor"));
 		start = cursor->current_frame ;
-		end = session->current_end_frame();
+		end = _session->current_end_frame();
 	} else {
 		if (cursor->current_frame > 0) {
 			begin_reversible_command (_("select all before cursor"));
@@ -1216,7 +1216,7 @@ Editor::select_all_selectables_using_edit (bool after)
 	if (after) {
 		begin_reversible_command (_("select all after edit"));
 		start = get_preferred_edit_position();
-		end = session->current_end_frame();
+		end = _session->current_end_frame();
 	} else {
 		if ((end = get_preferred_edit_position()) > 1) {
 			begin_reversible_command (_("select all before edit"));
@@ -1314,7 +1314,7 @@ Editor::get_edit_op_range (nframes64_t& start, nframes64_t& end) const
 		}
 
 		start = selection->markers.front()->position();
-		end = session->audible_frame();
+		end = _session->audible_frame();
 
 	} else {
 
@@ -1323,10 +1323,10 @@ Editor::get_edit_op_range (nframes64_t& start, nframes64_t& end) const
 			if (selection->markers.empty()) {
 				/* use mouse + playhead */
 				start = m;
-				end = session->audible_frame();
+				end = _session->audible_frame();
 			} else {
 				/* use playhead + selected marker */
-				start = session->audible_frame();
+				start = _session->audible_frame();
 				end = selection->markers.front()->position();
 			}
 			break;
@@ -1335,7 +1335,7 @@ Editor::get_edit_op_range (nframes64_t& start, nframes64_t& end) const
 			/* use mouse + selected marker */
 			if (selection->markers.empty()) {
 				start = m;
-				end = session->audible_frame();
+				end = _session->audible_frame();
 			} else {
 				start = selection->markers.front()->position();
 				end = m;
diff --git a/gtk2_ardour/editor_snapshots.cc b/gtk2_ardour/editor_snapshots.cc
index 8b544508d7..795ba425ea 100644
--- a/gtk2_ardour/editor_snapshots.cc
+++ b/gtk2_ardour/editor_snapshots.cc
@@ -52,9 +52,9 @@ EditorSnapshots::EditorSnapshots (Editor* e)
 }
 
 void
-EditorSnapshots::connect_to_session (Session* s)
+EditorSnapshots::set_session (Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
 	redisplay ();
 }
diff --git a/gtk2_ardour/editor_snapshots.h b/gtk2_ardour/editor_snapshots.h
index 1a17e6de30..5563778aa5 100644
--- a/gtk2_ardour/editor_snapshots.h
+++ b/gtk2_ardour/editor_snapshots.h
@@ -28,7 +28,7 @@ class EditorSnapshots : public EditorComponent
 public:
 	EditorSnapshots (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	Gtk::Widget& widget () {
 		return _scroller;
diff --git a/gtk2_ardour/editor_summary.cc b/gtk2_ardour/editor_summary.cc
index d257889682..b002150622 100644
--- a/gtk2_ardour/editor_summary.cc
+++ b/gtk2_ardour/editor_summary.cc
@@ -54,15 +54,18 @@ EditorSummary::EditorSummary (Editor* e)
  *  @param s Session.
  */
 void
-EditorSummary::connect_to_session (Session* s)
+EditorSummary::set_session (Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
 	Region::RegionPropertyChanged.connect (sigc::hide (sigc::mem_fun (*this, &EditorSummary::set_dirty)));
 
-	_session_connections.push_back (_session->RegionRemoved.connect (sigc::hide (sigc::mem_fun (*this, &EditorSummary::set_dirty))));
-	_session_connections.push_back (_session->StartTimeChanged.connect (sigc::mem_fun (*this, &EditorSummary::set_dirty)));
-	_session_connections.push_back (_session->EndTimeChanged.connect (sigc::mem_fun (*this, &EditorSummary::set_dirty)));
+	if (_session) {
+		_session_connections.add_connection (_session->RegionRemoved.connect (boost::bind (&EditorSummary::set_dirty, this)));
+		_session_connections.add_connection (_session->StartTimeChanged.connect (boost::bind (&EditorSummary::set_dirty, this)));
+		_session_connections.add_connection (_session->EndTimeChanged.connect (boost::bind (&EditorSummary::set_dirty, this)));
+	}
+
 	_editor->playhead_cursor->PositionChanged.connect (sigc::mem_fun (*this, &EditorSummary::playhead_position_changed));
 
 	set_dirty ();
diff --git a/gtk2_ardour/editor_summary.h b/gtk2_ardour/editor_summary.h
index e52e24cd99..9d9763996e 100644
--- a/gtk2_ardour/editor_summary.h
+++ b/gtk2_ardour/editor_summary.h
@@ -37,7 +37,7 @@ class EditorSummary : public CairoWidget, public EditorComponent
 public:
 	EditorSummary (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 	void set_overlays_dirty ();
 
 private:
diff --git a/gtk2_ardour/editor_tempodisplay.cc b/gtk2_ardour/editor_tempodisplay.cc
index 7fecf61be3..438f18b91e 100644
--- a/gtk2_ardour/editor_tempodisplay.cc
+++ b/gtk2_ardour/editor_tempodisplay.cc
@@ -95,7 +95,7 @@ Editor::draw_metric_marks (const Metrics& metrics)
 void
 Editor::tempo_map_changed (Change ignored)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -105,14 +105,14 @@ Editor::tempo_map_changed (Change ignored)
 		tempo_lines->tempo_map_changed();
 
 	compute_current_bbt_points(leftmost_frame, leftmost_frame + current_page_frames());
-	session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks); // redraw metric markers
+	_session->tempo_map().apply_with_metrics (*this, &Editor::draw_metric_marks); // redraw metric markers
 	redraw_measures ();
 }
 
 void
 Editor::redisplay_tempo (bool immediate_redraw)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -134,14 +134,14 @@ Editor::redisplay_tempo (bool immediate_redraw)
 void
 Editor::compute_current_bbt_points (nframes_t leftmost, nframes_t rightmost)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
 	BBT_Time previous_beat, next_beat; // the beats previous to the leftmost frame and after the rightmost frame
 
-	session->bbt_time(leftmost, previous_beat);
-	session->bbt_time(rightmost, next_beat);
+	_session->bbt_time(leftmost, previous_beat);
+	_session->bbt_time(rightmost, next_beat);
 
 	if (previous_beat.beats > 1) {
 		previous_beat.beats -= 1;
@@ -151,7 +151,7 @@ Editor::compute_current_bbt_points (nframes_t leftmost, nframes_t rightmost)
 	}
 	previous_beat.ticks = 0;
 
-	if (session->tempo_map().meter_at(rightmost).beats_per_bar () > next_beat.beats + 1) {
+	if (_session->tempo_map().meter_at(rightmost).beats_per_bar () > next_beat.beats + 1) {
 		next_beat.beats += 1;
 	} else {
 		next_beat.bars += 1;
@@ -162,7 +162,7 @@ Editor::compute_current_bbt_points (nframes_t leftmost, nframes_t rightmost)
 	delete current_bbt_points;
 	current_bbt_points = 0;
 
-	current_bbt_points = session->tempo_map().get_points (session->tempo_map().frame_time (previous_beat), session->tempo_map().frame_time (next_beat) + 1);
+	current_bbt_points = _session->tempo_map().get_points (_session->tempo_map().frame_time (previous_beat), _session->tempo_map().frame_time (next_beat) + 1);
 }
 
 void
@@ -182,7 +182,7 @@ Editor::redraw_measures ()
 void
 Editor::draw_measures ()
 {
-	if (session == 0 || _show_measures == false ||
+	if (_session == 0 || _show_measures == false ||
 	    !current_bbt_points || current_bbt_points->empty()) {
 		return;
 	}
@@ -197,11 +197,11 @@ Editor::draw_measures ()
 void
 Editor::mouse_add_new_tempo_event (nframes64_t frame)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
-	TempoMap& map(session->tempo_map());
+	TempoMap& map(_session->tempo_map());
 	TempoDialog tempo_dialog (map, frame, _("add"));
 
 	tempo_dialog.set_position (Gtk::WIN_POS_MOUSE);
@@ -230,7 +230,7 @@ Editor::mouse_add_new_tempo_event (nframes64_t frame)
         XMLNode &before = map.get_state();
 	map.add_tempo (Tempo (bpm,nt), requested);
         XMLNode &after = map.get_state();
-	session->add_command(new MementoCommand<TempoMap>(map, &before, &after));
+	_session->add_command(new MementoCommand<TempoMap>(map, &before, &after));
 	commit_reversible_command ();
 
 	//map.dump (cerr);
@@ -239,12 +239,12 @@ Editor::mouse_add_new_tempo_event (nframes64_t frame)
 void
 Editor::mouse_add_new_meter_event (nframes64_t frame)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return;
 	}
 
 
-	TempoMap& map(session->tempo_map());
+	TempoMap& map(_session->tempo_map());
 	MeterDialog meter_dialog (map, frame, _("add"));
 
 	meter_dialog.set_position (Gtk::WIN_POS_MOUSE);
@@ -272,7 +272,7 @@ Editor::mouse_add_new_meter_event (nframes64_t frame)
 	begin_reversible_command (_("add meter mark"));
         XMLNode &before = map.get_state();
 	map.add_meter (Meter (bpb, note_type), requested);
-	session->add_command(new MementoCommand<TempoMap>(map, &before, &map.get_state()));
+	_session->add_command(new MementoCommand<TempoMap>(map, &before, &map.get_state()));
 	commit_reversible_command ();
 
 	//map.dump (cerr);
@@ -321,10 +321,10 @@ Editor::edit_meter_section (MeterSection* section)
 	double note_type = meter_dialog.get_note_type ();
 
 	begin_reversible_command (_("replace tempo mark"));
-        XMLNode &before = session->tempo_map().get_state();
-	session->tempo_map().replace_meter (*section, Meter (bpb, note_type));
-        XMLNode &after = session->tempo_map().get_state();
-	session->add_command(new MementoCommand<TempoMap>(session->tempo_map(), &before, &after));
+        XMLNode &before = _session->tempo_map().get_state();
+	_session->tempo_map().replace_meter (*section, Meter (bpb, note_type));
+        XMLNode &after = _session->tempo_map().get_state();
+	_session->add_command(new MementoCommand<TempoMap>(_session->tempo_map(), &before, &after));
 	commit_reversible_command ();
 }
 
@@ -351,15 +351,15 @@ Editor::edit_tempo_section (TempoSection* section)
 	bpm = max (0.01, bpm);
 
 	cerr << "Editing tempo section to be at " << when << endl;
-	session->tempo_map().dump (cerr);
+	_session->tempo_map().dump (cerr);
 	begin_reversible_command (_("replace tempo mark"));
-	XMLNode &before = session->tempo_map().get_state();
-	session->tempo_map().replace_tempo (*section, Tempo (bpm,nt));
-	session->tempo_map().dump (cerr);
-	session->tempo_map().move_tempo (*section, when);
-	session->tempo_map().dump (cerr);
-	XMLNode &after = session->tempo_map().get_state();
-	session->add_command (new MementoCommand<TempoMap>(session->tempo_map(), &before, &after));
+	XMLNode &before = _session->tempo_map().get_state();
+	_session->tempo_map().replace_tempo (*section, Tempo (bpm,nt));
+	_session->tempo_map().dump (cerr);
+	_session->tempo_map().move_tempo (*section, when);
+	_session->tempo_map().dump (cerr);
+	XMLNode &after = _session->tempo_map().get_state();
+	_session->add_command (new MementoCommand<TempoMap>(_session->tempo_map(), &before, &after));
 	commit_reversible_command ();
 }
 
@@ -405,10 +405,10 @@ gint
 Editor::real_remove_tempo_marker (TempoSection *section)
 {
 	begin_reversible_command (_("remove tempo mark"));
-	XMLNode &before = session->tempo_map().get_state();
-	session->tempo_map().remove_tempo (*section);
-	XMLNode &after = session->tempo_map().get_state();
-	session->add_command(new MementoCommand<TempoMap>(session->tempo_map(), &before, &after));
+	XMLNode &before = _session->tempo_map().get_state();
+	_session->tempo_map().remove_tempo (*section);
+	XMLNode &after = _session->tempo_map().get_state();
+	_session->add_command(new MementoCommand<TempoMap>(_session->tempo_map(), &before, &after));
 	commit_reversible_command ();
 
 	return FALSE;
@@ -439,10 +439,10 @@ gint
 Editor::real_remove_meter_marker (MeterSection *section)
 {
 	begin_reversible_command (_("remove tempo mark"));
-	XMLNode &before = session->tempo_map().get_state();
-	session->tempo_map().remove_meter (*section);
-	XMLNode &after = session->tempo_map().get_state();
-	session->add_command(new MementoCommand<TempoMap>(session->tempo_map(), &before, &after));
+	XMLNode &before = _session->tempo_map().get_state();
+	_session->tempo_map().remove_meter (*section);
+	XMLNode &after = _session->tempo_map().get_state();
+	_session->add_command(new MementoCommand<TempoMap>(_session->tempo_map(), &before, &after));
 	commit_reversible_command ();
 
 	return FALSE;
diff --git a/gtk2_ardour/editor_timefx.cc b/gtk2_ardour/editor_timefx.cc
index 8538c7b8b3..aab6b67658 100644
--- a/gtk2_ardour/editor_timefx.cc
+++ b/gtk2_ardour/editor_timefx.cc
@@ -77,14 +77,14 @@ Editor::time_stretch (RegionSelection& regions, float fraction)
 
 	    ARDOUR::TimeFXRequest request;
 		request.time_fraction = fraction;
-		MidiStretch stretch(*session, request);
+		MidiStretch stretch(*_session, request);
 		begin_reversible_command ("midi stretch");
 		stretch.run(regions.front()->region());
 		XMLNode &before = playlist->get_state();
 		playlist->replace_region (regions.front()->region(), stretch.results[0],
 				regions.front()->region()->position());
 		XMLNode &after = playlist->get_state();
-		session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
+		_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
 		commit_reversible_command ();
 	}
 
@@ -291,12 +291,12 @@ Editor::do_timefx (TimeFXDialog& dialog)
 		Filter* fx;
 
 		if (dialog.pitching) {
-			fx = new Pitch (*session, dialog.request);
+			fx = new Pitch (*_session, dialog.request);
 		} else {
 #ifdef USE_RUBBERBAND
-			fx = new RBStretch (*session, dialog.request);
+			fx = new RBStretch (*_session, dialog.request);
 #else
-			fx = new STStretch (*session, dialog.request);
+			fx = new STStretch (*_session, dialog.request);
 #endif
 		}
 
@@ -311,14 +311,14 @@ Editor::do_timefx (TimeFXDialog& dialog)
 			new_region = fx->results.front();
 
 			if (!in_command) {
-				session->begin_reversible_command (dialog.pitching ? _("pitch shift") : _("time stretch"));
+				_session->begin_reversible_command (dialog.pitching ? _("pitch shift") : _("time stretch"));
 				in_command = true;
 			}
 
 			XMLNode &before = playlist->get_state();
 			playlist->replace_region (region, new_region, region->position());
 			XMLNode &after = playlist->get_state();
-			session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
+			_session->add_command (new MementoCommand<Playlist>(*playlist, &before, &after));
 		}
 
 		i = tmp;
@@ -326,7 +326,7 @@ Editor::do_timefx (TimeFXDialog& dialog)
 	}
 
 	if (in_command) {
-		session->commit_reversible_command ();
+		_session->commit_reversible_command ();
 	}
 
 	dialog.status = 0;
diff --git a/gtk2_ardour/export_channel_selector.cc b/gtk2_ardour/export_channel_selector.cc
index 17f2ad59ea..74a18b9770 100644
--- a/gtk2_ardour/export_channel_selector.cc
+++ b/gtk2_ardour/export_channel_selector.cc
@@ -108,11 +108,11 @@ void
 PortExportChannelSelector::fill_route_list ()
 {
 	channel_view.clear_routes ();
-	RouteList routes = *session->get_routes();
+	RouteList routes = *_session->get_routes();
 
 	/* Add master bus and then everything else */
 
-	ARDOUR::IO* master = session->master_out()->output().get();
+	ARDOUR::IO* master = _session->master_out()->output().get();
 	channel_view.add_route (master);
 
 	for (RouteList::iterator it = routes.begin(); it != routes.end(); ++it) {
@@ -435,11 +435,11 @@ PortExportChannelSelector::ChannelTreeView::update_selection_text (Glib::ustring
 	update_config ();
 }
 
-RegionExportChannelSelector::RegionExportChannelSelector (ARDOUR::Session * session,
+RegionExportChannelSelector::RegionExportChannelSelector (ARDOUR::Session * _session,
                                                           ProfileManagerPtr manager,
                                                           ARDOUR::AudioRegion const & region,
                                                           ARDOUR::AudioTrack & track) :
-  ExportChannelSelector (session, manager),
+  ExportChannelSelector (_session, manager),
   region (region),
   track (track),
   region_chans (region.n_channels()),
@@ -485,11 +485,11 @@ RegionExportChannelSelector::handle_selection ()
 	state->config->clear_channels ();
 
 	if (raw_button.get_active ()) {
-		factory.reset (new RegionExportChannelFactory (session, region, track, RegionExportChannelFactory::Raw));
+		factory.reset (new RegionExportChannelFactory (_session, region, track, RegionExportChannelFactory::Raw));
 	} else if (fades_button.get_active ()) {
-		factory.reset (new RegionExportChannelFactory (session, region, track, RegionExportChannelFactory::Fades));
+		factory.reset (new RegionExportChannelFactory (_session, region, track, RegionExportChannelFactory::Fades));
 	} else if (processed_button.get_active ()) {
-		factory.reset (new RegionExportChannelFactory(session, region, track, RegionExportChannelFactory::Processed));
+		factory.reset (new RegionExportChannelFactory(_session, region, track, RegionExportChannelFactory::Processed));
 	} else {
 		CriticalSelectionChanged ();
 		return;
diff --git a/gtk2_ardour/export_channel_selector.h b/gtk2_ardour/export_channel_selector.h
index 56ce5c9501..6a1c4252a4 100644
--- a/gtk2_ardour/export_channel_selector.h
+++ b/gtk2_ardour/export_channel_selector.h
@@ -43,19 +43,18 @@ namespace ARDOUR {
 
 class XMLNode;
 
-class ExportChannelSelector : public Gtk::HBox
+class ExportChannelSelector : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   protected:
 	typedef boost::shared_ptr<ARDOUR::ExportChannelConfiguration> ChannelConfigPtr;
 	typedef boost::shared_ptr<ARDOUR::ExportProfileManager> ProfileManagerPtr;
 
-	ARDOUR::Session * session;
 	ProfileManagerPtr manager;
 
   public:
 	ExportChannelSelector (ARDOUR::Session * session, ProfileManagerPtr manager)
-	  : session (session)
-	  , manager (manager)
+		: SessionHandlePtr (session)
+		, manager (manager)
 	{}
 
 	virtual ~ExportChannelSelector () {}
diff --git a/gtk2_ardour/export_dialog.cc b/gtk2_ardour/export_dialog.cc
index c0e595fd00..1ec466d449 100644
--- a/gtk2_ardour/export_dialog.cc
+++ b/gtk2_ardour/export_dialog.cc
@@ -45,22 +45,26 @@ ExportDialog::~ExportDialog ()
 void
 ExportDialog::set_session (ARDOUR::Session* s)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
+
+	if (!_session) {
+		return;
+	}
 
 	/* Init handler and profile manager */
 
-	handler = session->get_export_handler ();
-	status = session->get_export_status ();
-	profile_manager.reset (new ExportProfileManager (*session));
+	handler = _session->get_export_handler ();
+	status = _session->get_export_status ();
+	profile_manager.reset (new ExportProfileManager (*_session));
 
 	/* Possibly init stuff in derived classes */
 
 	init ();
 
-	/* Rest of session related initialization */
+	/* Rest of _session related initialization */
 
 	preset_selector->set_manager (profile_manager);
-	file_notebook->set_session_and_manager (session, profile_manager);
+	file_notebook->set_session_and_manager (_session, profile_manager);
 
 	/* Hand on selection range to profile manager  */
 
@@ -177,8 +181,8 @@ void
 ExportDialog::init_components ()
 {
 	preset_selector.reset (new ExportPresetSelector ());
-	timespan_selector.reset (new ExportTimespanSelectorMultiple (session, profile_manager));
-	channel_selector.reset (new PortExportChannelSelector (session, profile_manager));
+	timespan_selector.reset (new ExportTimespanSelectorMultiple (_session, profile_manager));
+	channel_selector.reset (new PortExportChannelSelector (_session, profile_manager));
 	file_notebook.reset (new ExportFileNotebook ());
 }
 
@@ -372,8 +376,8 @@ void
 ExportRangeDialog::init_components ()
 {
 	preset_selector.reset (new ExportPresetSelector ());
-	timespan_selector.reset (new ExportTimespanSelectorSingle (session, profile_manager, range_id));
-	channel_selector.reset (new PortExportChannelSelector (session, profile_manager));
+	timespan_selector.reset (new ExportTimespanSelectorSingle (_session, profile_manager, range_id));
+	channel_selector.reset (new PortExportChannelSelector (_session, profile_manager));
 	file_notebook.reset (new ExportFileNotebook ());
 }
 
@@ -385,8 +389,8 @@ void
 ExportSelectionDialog::init_components ()
 {
 	preset_selector.reset (new ExportPresetSelector ());
-	timespan_selector.reset (new ExportTimespanSelectorSingle (session, profile_manager, X_("selection")));
-	channel_selector.reset (new PortExportChannelSelector (session, profile_manager));
+	timespan_selector.reset (new ExportTimespanSelectorSingle (_session, profile_manager, X_("selection")));
+	channel_selector.reset (new PortExportChannelSelector (_session, profile_manager));
 	file_notebook.reset (new ExportFileNotebook ());
 }
 
@@ -410,7 +414,7 @@ ExportRegionDialog::init_components ()
 	Glib::ustring loc_id = profile_manager->set_single_range (region.position(), region.position() + region.length(), region.name());
 
 	preset_selector.reset (new ExportPresetSelector ());
-	timespan_selector.reset (new ExportTimespanSelectorSingle (session, profile_manager, loc_id));
-	channel_selector.reset (new RegionExportChannelSelector (session, profile_manager, region, track));
+	timespan_selector.reset (new ExportTimespanSelectorSingle (_session, profile_manager, loc_id));
+	channel_selector.reset (new RegionExportChannelSelector (_session, profile_manager, region, track));
 	file_notebook.reset (new ExportFileNotebook ());
 }
diff --git a/gtk2_ardour/export_file_notebook.cc b/gtk2_ardour/export_file_notebook.cc
index ab9a22ee28..93a78cdad2 100644
--- a/gtk2_ardour/export_file_notebook.cc
+++ b/gtk2_ardour/export_file_notebook.cc
@@ -49,7 +49,7 @@ ExportFileNotebook::ExportFileNotebook () :
 void
 ExportFileNotebook::set_session_and_manager (ARDOUR::Session * s, boost::shared_ptr<ARDOUR::ExportProfileManager> manager)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
 	profile_manager = manager;
 
 	sync_with_manager ();
@@ -110,7 +110,7 @@ ExportFileNotebook::add_new_file_page ()
 void
 ExportFileNotebook::add_file_page (ARDOUR::ExportProfileManager::FormatStatePtr format_state, ARDOUR::ExportProfileManager::FilenameStatePtr filename_state)
 {
-	FilePage * page = Gtk::manage (new FilePage (session, profile_manager, this, page_counter, format_state, filename_state));
+	FilePage * page = Gtk::manage (new FilePage (_session, profile_manager, this, page_counter, format_state, filename_state));
 	page->CriticalSelectionChanged.connect (CriticalSelectionChanged.make_slot());
 	insert_page (*page, page->get_tab_widget(), get_n_pages() - 1);
 
diff --git a/gtk2_ardour/export_file_notebook.h b/gtk2_ardour/export_file_notebook.h
index 4eed7dc200..720c3b4bfd 100644
--- a/gtk2_ardour/export_file_notebook.h
+++ b/gtk2_ardour/export_file_notebook.h
@@ -25,16 +25,12 @@
 #include <gtkmm.h>
 
 #include "ardour/export_profile_manager.h"
+#include "ardour/session_handle.h"
 
 #include "export_format_selector.h"
 #include "export_filename_selector.h"
 
-namespace ARDOUR {
-	class Session;
-}
-
-
-class ExportFileNotebook : public Gtk::Notebook
+class ExportFileNotebook : public Gtk::Notebook, public ARDOUR::SessionHandlePtr
 {
   public:
 
@@ -55,7 +51,6 @@ class ExportFileNotebook : public Gtk::Notebook
 	class FilePage;
 
 	ManagerPtr        profile_manager;
-	ARDOUR::Session * session;
 
 	void add_new_file_page ();
 	void add_file_page (ARDOUR::ExportProfileManager::FormatStatePtr format_state, ARDOUR::ExportProfileManager::FilenameStatePtr filename_state);
diff --git a/gtk2_ardour/export_filename_selector.cc b/gtk2_ardour/export_filename_selector.cc
index 30a7fbce7f..abd057414a 100644
--- a/gtk2_ardour/export_filename_selector.cc
+++ b/gtk2_ardour/export_filename_selector.cc
@@ -29,16 +29,14 @@
 using namespace ARDOUR;
 
 ExportFilenameSelector::ExportFilenameSelector () :
-  session (0),
-
-  include_label (_("Include in Filename(s):"), Gtk::ALIGN_LEFT),
-
-  label_label (_("Label:"), Gtk::ALIGN_LEFT),
-  session_checkbox (_("Session Name")),
-  revision_checkbox (_("Revision:")),
-
-  path_label (_("Folder:"), Gtk::ALIGN_LEFT),
-  browse_button (_("Browse"))
+	include_label (_("Include in Filename(s):"), Gtk::ALIGN_LEFT),
+	
+	label_label (_("Label:"), Gtk::ALIGN_LEFT),
+	session_checkbox (_("Session Name")),
+	revision_checkbox (_("Revision:")),
+	
+	path_label (_("Folder:"), Gtk::ALIGN_LEFT),
+	browse_button (_("Browse"))
 {
 	pack_start (include_label, false, false, 6);
 	pack_start (include_hbox, false, false, 0);
@@ -136,7 +134,7 @@ ExportFilenameSelector::load_state ()
 void
 ExportFilenameSelector::set_state (ARDOUR::ExportProfileManager::FilenameStatePtr state_, ARDOUR::Session * session_)
 {
-	session = session_;
+	SessionHandlePtr::set_session (session_);
 
 	filename = state_->filename;
 
diff --git a/gtk2_ardour/export_filename_selector.h b/gtk2_ardour/export_filename_selector.h
index a6c36da83d..cfe909a46b 100644
--- a/gtk2_ardour/export_filename_selector.h
+++ b/gtk2_ardour/export_filename_selector.h
@@ -25,13 +25,11 @@
 
 #include "ardour/export_profile_manager.h"
 #include "ardour/export_filename.h"
-
-namespace ARDOUR {
-	class Session;
-}
+#include "ardour/session_handle.h"
 
 ///
-class ExportFilenameSelector : public Gtk::VBox {
+class ExportFilenameSelector : public Gtk::VBox, public ARDOUR::SessionHandlePtr 
+{
   public:
 	typedef boost::shared_ptr<ARDOUR::ExportFilename> FilenamePtr;
 
@@ -60,7 +58,6 @@ class ExportFilenameSelector : public Gtk::VBox {
 
 	void open_browse_dialog ();
 
-	ARDOUR::Session * session;
 	boost::shared_ptr<ARDOUR::ExportFilename> filename;
 
 	Glib::RefPtr<Gtk::SizeGroup> label_sizegroup;
diff --git a/gtk2_ardour/export_format_dialog.cc b/gtk2_ardour/export_format_dialog.cc
index 770e46de4b..05c1759867 100644
--- a/gtk2_ardour/export_format_dialog.cc
+++ b/gtk2_ardour/export_format_dialog.cc
@@ -194,14 +194,14 @@ ExportFormatDialog::revert ()
 void
 ExportFormatDialog::set_session (ARDOUR::Session* s)
 {
-	session = s;
-	if (!session) {
-		return;
-	}
-
+	SessionHandlePtr::set_session (s);
 	silence_start_clock.set_session (s);
 	silence_end_clock.set_session (s);
 
+	if (!_session) {
+		return;
+	}
+
 	update_clock (silence_start_clock, silence_start);
 	update_clock (silence_end_clock, silence_end);
 
@@ -210,7 +210,7 @@ ExportFormatDialog::set_session (ARDOUR::Session* s)
 	if (sample_rate_view.get_selection()->count_selected_rows() == 0) {
 		Gtk::ListStore::Children::iterator it;
 		for (it = sample_rate_list->children().begin(); it != sample_rate_list->children().end(); ++it) {
-			if ((nframes_t) (*it)->get_value (sample_rate_cols.ptr)->rate == session->nominal_frame_rate()) {
+			if ((nframes_t) (*it)->get_value (sample_rate_cols.ptr)->rate == _session->nominal_frame_rate()) {
 				sample_rate_view.get_selection()->select (it);
 				break;
 			}
@@ -586,8 +586,8 @@ ExportFormatDialog::change_sample_rate_selection (bool select, WeakSampleRatePtr
 
 	if (select) {
 		ExportFormatManager::SampleRatePtr ptr = rate.lock();
-		if (ptr && session) {
-			src_quality_combo.set_sensitive ((uint32_t) ptr->rate != session->frame_rate());
+		if (ptr && _session) {
+			src_quality_combo.set_sensitive ((uint32_t) ptr->rate != _session->frame_rate());
 		}
 	}
 }
@@ -728,7 +728,7 @@ void
 ExportFormatDialog::update_clock (AudioClock & clock, ARDOUR::AnyTime const & time)
 {
 	// TODO position
-	clock.set (session->convert_to_frames_at (0, time), true);
+	clock.set (_session->convert_to_frames_at (0, time), true);
 
 	AudioClock::Mode mode(AudioClock::Timecode);
 
@@ -753,7 +753,7 @@ ExportFormatDialog::update_clock (AudioClock & clock, ARDOUR::AnyTime const & ti
 void
 ExportFormatDialog::update_time (AnyTime & time, AudioClock const & clock)
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -762,15 +762,15 @@ ExportFormatDialog::update_time (AnyTime & time, AudioClock const & clock)
 	switch (clock.mode()) {
 	  case AudioClock::Timecode:
 		time.type = AnyTime::Timecode;
-		session->timecode_time (frames, time.timecode);
+		_session->timecode_time (frames, time.timecode);
 		break;
 	  case AudioClock::BBT:
 		time.type = AnyTime::BBT;
-		session->bbt_time (frames, time.bbt);
+		_session->bbt_time (frames, time.bbt);
 		break;
 	  case AudioClock::MinSec:
 		time.type = AnyTime::Seconds;
-		time.seconds = (double) frames / session->frame_rate();
+		time.seconds = (double) frames / _session->frame_rate();
 		break;
 	  case AudioClock::Frames:
 		time.type = AnyTime::Frames;
diff --git a/gtk2_ardour/export_format_selector.cc b/gtk2_ardour/export_format_selector.cc
index 002edaf50c..6b1f75987e 100644
--- a/gtk2_ardour/export_format_selector.cc
+++ b/gtk2_ardour/export_format_selector.cc
@@ -65,7 +65,8 @@ ExportFormatSelector::~ExportFormatSelector ()
 void
 ExportFormatSelector::set_state (ARDOUR::ExportProfileManager::FormatStatePtr const state_, ARDOUR::Session * session_)
 {
-	session = session_;
+	SessionHandlePtr::set_session (session_);
+
 	state = state_;
 
 	update_format_list ();
@@ -141,7 +142,7 @@ int
 ExportFormatSelector::open_edit_dialog (bool new_dialog)
 {
 	ExportFormatDialog dialog (state->format, new_dialog);
-	dialog.set_session (session);
+	dialog.set_session (_session);
 	Gtk::ResponseType response = (Gtk::ResponseType) dialog.run();
 	if (response == Gtk::RESPONSE_APPLY) {
 		update_format_description ();
diff --git a/gtk2_ardour/export_format_selector.h b/gtk2_ardour/export_format_selector.h
index 46d9bc3f06..6e1dd52786 100644
--- a/gtk2_ardour/export_format_selector.h
+++ b/gtk2_ardour/export_format_selector.h
@@ -27,14 +27,16 @@
 #include <sigc++/signal.h>
 #include <boost/shared_ptr.hpp>
 
+#include "ardour/session_handle.h"
+
 namespace ARDOUR {
-	class Session;
 	class ExportFormatSpecification;
 	class ExportProfileManager;
 }
 
 ///
-class ExportFormatSelector : public Gtk::HBox {
+class ExportFormatSelector : public Gtk::HBox, public ARDOUR::SessionHandlePtr
+{
 
   private:
 
@@ -67,7 +69,6 @@ class ExportFormatSelector : public Gtk::HBox {
 	void update_format_description ();
 
 	ARDOUR::ExportProfileManager::FormatStatePtr state;
-	ARDOUR::Session * session;
 
 	/*** GUI componenets ***/
 
diff --git a/gtk2_ardour/export_timespan_selector.cc b/gtk2_ardour/export_timespan_selector.cc
index 30515d45fd..9f39fa556c 100644
--- a/gtk2_ardour/export_timespan_selector.cc
+++ b/gtk2_ardour/export_timespan_selector.cc
@@ -41,10 +41,10 @@ using namespace ARDOUR;
 using namespace PBD;
 
 ExportTimespanSelector::ExportTimespanSelector (ARDOUR::Session * session, ProfileManagerPtr manager) :
-  session (session),
-  manager (manager),
-  time_format_label (_("Show Times as:"), Gtk::ALIGN_LEFT)
+	manager (manager),
+	time_format_label (_("Show Times as:"), Gtk::ALIGN_LEFT)
 {
+	set_session (session);
 
 	option_hbox.pack_start (time_format_label, false, false, 0);
 	option_hbox.pack_start (time_format_combo, false, false, 6);
@@ -100,7 +100,7 @@ ExportTimespanSelector::~ExportTimespanSelector ()
 void
 ExportTimespanSelector::add_range_to_selection (ARDOUR::Location const * loc)
 {
-	TimespanPtr span = session->get_export_handler()->add_timespan();
+	TimespanPtr span = _session->get_export_handler()->add_timespan();
 
 	Glib::ustring id;
 	if (loc == state->session_range.get()) {
@@ -201,14 +201,14 @@ ExportTimespanSelector::construct_label (ARDOUR::Location const * location) cons
 Glib::ustring
 ExportTimespanSelector::bbt_str (nframes_t frames) const
 {
-	if (!session) {
+	if (!_session) {
 		return "Error!";
 	}
 
 	std::ostringstream oss;
 	BBT_Time time;
 
-	session->bbt_time (frames, time);
+	_session->bbt_time (frames, time);
 
 	oss << std::setfill('0') << std::right <<
 	  std::setw(3) <<
@@ -224,14 +224,14 @@ ExportTimespanSelector::bbt_str (nframes_t frames) const
 Glib::ustring
 ExportTimespanSelector::timecode_str (nframes_t frames) const
 {
-	if (!session) {
+	if (!_session) {
 		return "Error!";
 	}
 
 	std::ostringstream oss;
 	Timecode::Time time;
 
-	session->timecode_time (frames, time);
+	_session->timecode_time (frames, time);
 
 	oss << std::setfill('0') << std::right <<
 	  std::setw(2) <<
@@ -249,7 +249,7 @@ ExportTimespanSelector::timecode_str (nframes_t frames) const
 Glib::ustring
 ExportTimespanSelector::ms_str (nframes_t frames) const
 {
-	if (!session) {
+	if (!_session) {
 		return "Error!";
 	}
 
@@ -261,13 +261,13 @@ ExportTimespanSelector::ms_str (nframes_t frames) const
 	int sec_promilles;
 
 	left = frames;
-	hrs = (int) floor (left / (session->frame_rate() * 60.0f * 60.0f));
-	left -= (nframes_t) floor (hrs * session->frame_rate() * 60.0f * 60.0f);
-	mins = (int) floor (left / (session->frame_rate() * 60.0f));
-	left -= (nframes_t) floor (mins * session->frame_rate() * 60.0f);
-	secs = (int) floor (left / (float) session->frame_rate());
-	left -= (nframes_t) floor (secs * session->frame_rate());
-	sec_promilles = (int) (left * 1000 / (float) session->frame_rate() + 0.5);
+	hrs = (int) floor (left / (_session->frame_rate() * 60.0f * 60.0f));
+	left -= (nframes_t) floor (hrs * _session->frame_rate() * 60.0f * 60.0f);
+	mins = (int) floor (left / (_session->frame_rate() * 60.0f));
+	left -= (nframes_t) floor (mins * _session->frame_rate() * 60.0f);
+	secs = (int) floor (left / (float) _session->frame_rate());
+	left -= (nframes_t) floor (secs * _session->frame_rate());
+	sec_promilles = (int) (left * 1000 / (float) _session->frame_rate() + 0.5);
 
 	oss << std::setfill('0') << std::right <<
 	  std::setw(2) <<
@@ -294,8 +294,8 @@ ExportTimespanSelector::update_range_name (Glib::ustring const & path, Glib::ust
 /*** ExportTimespanSelectorSingle ***/
 
 ExportTimespanSelectorSingle::ExportTimespanSelectorSingle (ARDOUR::Session * session, ProfileManagerPtr manager, Glib::ustring range_id) :
-  ExportTimespanSelector (session, manager),
-  range_id (range_id)
+	ExportTimespanSelector (session, manager),
+	range_id (range_id)
 {
 	range_scroller.set_policy (Gtk::POLICY_NEVER, Gtk::POLICY_NEVER);
 	range_view.append_column_editable ("", range_cols.name);
diff --git a/gtk2_ardour/export_timespan_selector.h b/gtk2_ardour/export_timespan_selector.h
index ad57aac344..5d299e1e52 100644
--- a/gtk2_ardour/export_timespan_selector.h
+++ b/gtk2_ardour/export_timespan_selector.h
@@ -30,19 +30,20 @@
 #include <boost/shared_ptr.hpp>
 
 #include "ardour/types.h"
+#include "ardour/session_handle.h"
 #include "ardour/export_profile_manager.h"
 
 namespace ARDOUR {
 	class Location;
 	class ExportTimespan;
 	class ExportHandler;
-	class Session;
 }
 
 using ARDOUR::CDMarkerFormat;
 
 /// Timespan Selector base
-class ExportTimespanSelector : public Gtk::VBox {
+class ExportTimespanSelector : public Gtk::VBox, public ARDOUR::SessionHandlePtr
+{
   protected:
 	typedef std::list<ARDOUR::Location *> LocationList;
 	typedef boost::shared_ptr<ARDOUR::ExportHandler> HandlerPtr;
@@ -65,7 +66,6 @@ class ExportTimespanSelector : public Gtk::VBox {
 
   protected:
 
-	ARDOUR::Session * session;
 	ProfileManagerPtr manager;
 	TimespanStatePtr  state;
 
diff --git a/gtk2_ardour/gain_meter.cc b/gtk2_ardour/gain_meter.cc
index 950071ba13..26036f6e66 100644
--- a/gtk2_ardour/gain_meter.cc
+++ b/gtk2_ardour/gain_meter.cc
@@ -74,13 +74,11 @@ GainMeter::setup_slider_pix ()
 	}
 }
 
-GainMeterBase::GainMeterBase (Session& s,
+GainMeterBase::GainMeterBase (Session* s,
 			      const Glib::RefPtr<Gdk::Pixbuf>& pix,
 			      bool horizontal,
 			      int fader_length)
-	: _session (s)
-	  // 0.781787 is the value needed for gain to be set to 0.
-	, gain_adjustment (0.781787, 0.0, 1.0, 0.01, 0.1)
+	: gain_adjustment (0.781787, 0.0, 1.0, 0.01, 0.1)  // 0.781787 is the value needed for gain to be set to 0.
 	, gain_automation_style_button ("")
 	, gain_automation_state_button ("")
 	, dpi_changed (false)
@@ -89,6 +87,8 @@ GainMeterBase::GainMeterBase (Session& s,
 {
 	using namespace Menu_Helpers;
 
+	set_session (s);
+
 	ignore_toggle = false;
 	meter_menu = 0;
 	next_release_selects = false;
@@ -170,6 +170,7 @@ GainMeterBase::set_controls (boost::shared_ptr<Route> r,
 			     boost::shared_ptr<Amp> amp)
 {
  	connections.clear ();
+	model_connections.drop_connections ();
 
 	if (!pm && !amp) {
 		level_meter->set_meter (0);
@@ -224,14 +225,14 @@ GainMeterBase::set_controls (boost::shared_ptr<Route> r,
 		connections.push_back (gain_automation_state_button.signal_button_press_event().connect (sigc::mem_fun(*this, &GainMeterBase::gain_automation_state_button_event), false));
 
 		boost::shared_ptr<AutomationControl> gc = amp->gain_control();
-
-		connections.push_back (gc->alist()->automation_state_changed.connect (sigc::mem_fun(*this, &GainMeter::gain_automation_state_changed)));
-		connections.push_back (gc->alist()->automation_style_changed.connect (sigc::mem_fun(*this, &GainMeter::gain_automation_style_changed)));
-
+		
+		model_connections.add_connection (gc->alist()->automation_state_changed.connect (boost::bind (&GainMeter::gain_automation_state_changed, this)));
+		model_connections.add_connection (gc->alist()->automation_style_changed.connect (boost::bind (&GainMeter::gain_automation_style_changed, this)));
+		
 		gain_automation_state_changed ();
 	}
-
-	connections.push_back (amp->gain_control()->Changed.connect (sigc::mem_fun (*this, &GainMeterBase::gain_changed)));
+	
+	model_connections.add_connection (amp->gain_control()->Changed.connect (boost::bind (&GainMeterBase::gain_changed, this)));
 
 	gain_changed ();
 	show_gain ();
@@ -518,7 +519,7 @@ GainMeterBase::meter_press(GdkEventButton* ev)
 
 					/* Primary+Tertiary-click applies change to all routes */
 
-					_session.foreach_route (this, &GainMeterBase::set_meter_point, next_meter_point (_route->meter_point()));
+					_session->foreach_route (this, &GainMeterBase::set_meter_point, next_meter_point (_route->meter_point()));
 
 
 				} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
@@ -787,7 +788,7 @@ GainMeterBase::on_theme_changed()
 	style_changed = true;
 }
 
-GainMeter::GainMeter (Session& s, int fader_length)
+GainMeter::GainMeter (Session* s, int fader_length)
 	: GainMeterBase (s, slider, false, fader_length)
 {
 	gain_display_box.set_homogeneous (true);
diff --git a/gtk2_ardour/gain_meter.h b/gtk2_ardour/gain_meter.h
index 448e0239fe..16c818dead 100644
--- a/gtk2_ardour/gain_meter.h
+++ b/gtk2_ardour/gain_meter.h
@@ -32,11 +32,14 @@
 #include <gtkmm/drawingarea.h>
 #include <gdkmm/colormap.h>
 
+#include "pbd/scoped_connections.h"
+
 #include "ardour/types.h"
+#include "ardour/session_handle.h"
 
-#include <gtkmm2ext/click_box.h>
-#include <gtkmm2ext/focus_entry.h>
-#include <gtkmm2ext/slider_controller.h>
+#include "gtkmm2ext/click_box.h"
+#include "gtkmm2ext/focus_entry.h"
+#include "gtkmm2ext/slider_controller.h"
 
 #include "enums.h"
 #include "level_meter.h"
@@ -58,10 +61,10 @@ namespace Gtk {
 	class Menu;
 }
 
-class GainMeterBase : virtual public sigc::trackable
+class GainMeterBase : virtual public sigc::trackable, ARDOUR::SessionHandlePtr
 {
   public:
-	GainMeterBase (ARDOUR::Session&, const Glib::RefPtr<Gdk::Pixbuf>& pix,
+	GainMeterBase (ARDOUR::Session*, const Glib::RefPtr<Gdk::Pixbuf>& pix,
 		       bool horizontal, int);
 	virtual ~GainMeterBase ();
 
@@ -90,8 +93,8 @@ class GainMeterBase : virtual public sigc::trackable
 	boost::shared_ptr<ARDOUR::Route> _route;
 	boost::shared_ptr<ARDOUR::PeakMeter> _meter;
 	boost::shared_ptr<ARDOUR::Amp> _amp;
-	ARDOUR::Session& _session;
 	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList model_connections;
 
 	bool ignore_toggle;
 	bool next_release_selects;
@@ -180,7 +183,7 @@ class GainMeterBase : virtual public sigc::trackable
 class GainMeter : public GainMeterBase, public Gtk::VBox
 {
   public:
-	GainMeter (ARDOUR::Session&, int);
+	GainMeter (ARDOUR::Session*, int);
 	~GainMeter () {}
 
 	virtual void set_controls (boost::shared_ptr<ARDOUR::Route> route,
diff --git a/gtk2_ardour/ghostregion.cc b/gtk2_ardour/ghostregion.cc
index 9fb0deb98a..c7a10636ff 100644
--- a/gtk2_ardour/ghostregion.cc
+++ b/gtk2_ardour/ghostregion.cc
@@ -34,6 +34,8 @@ using namespace Editing;
 using namespace ArdourCanvas;
 using namespace ARDOUR;
 
+boost::signals2::signal<void(GhostRegion*)> GhostRegion::GoingAway;
+
 GhostRegion::GhostRegion (ArdourCanvas::Group* parent, TimeAxisView& tv, TimeAxisView& source_tv, double initial_pos)
 	: trackview (tv)
 	, source_trackview (source_tv)
diff --git a/gtk2_ardour/ghostregion.h b/gtk2_ardour/ghostregion.h
index b28607e6f2..0932594a6f 100644
--- a/gtk2_ardour/ghostregion.h
+++ b/gtk2_ardour/ghostregion.h
@@ -21,8 +21,8 @@
 #define __ardour_gtk_ghost_region_h__
 
 #include <vector>
-#include <sigc++/signal.h>
 #include <libgnomecanvasmm.h>
+#include <boost/signals2.hpp>
 #include "canvas.h"
 
 namespace Gnome {
@@ -37,7 +37,7 @@ namespace Gnome {
 class MidiStreamView;
 class TimeAxisView;
 
-class GhostRegion : public sigc::trackable
+class GhostRegion 
 {
 public:
 	GhostRegion(ArdourCanvas::Group* parent, TimeAxisView& tv, TimeAxisView& source_tv, double initial_unit_pos);
@@ -52,12 +52,12 @@ public:
 	guint source_track_color(unsigned char alpha = 0xff);
 	bool is_automation_ghost();
 
-	sigc::signal<void,GhostRegion*> GoingAway;
-
 	TimeAxisView& trackview;
 	TimeAxisView& source_trackview;
 	ArdourCanvas::Group* group;
 	ArdourCanvas::SimpleRect* base_rect;
+
+	static boost::signals2::signal<void(GhostRegion*)> GoingAway;
 };
 
 class AudioGhostRegion : public GhostRegion {
diff --git a/gtk2_ardour/group_tabs.cc b/gtk2_ardour/group_tabs.cc
index 013df4255a..3a7206c9d4 100644
--- a/gtk2_ardour/group_tabs.cc
+++ b/gtk2_ardour/group_tabs.cc
@@ -40,11 +40,13 @@ GroupTabs::GroupTabs (Editor* e)
 }
 
 void
-GroupTabs::connect_to_session (Session* s)
+GroupTabs::set_session (Session* s)
 {
-	EditorComponent::connect_to_session (s);
+	EditorComponent::set_session (s);
 
-	_session_connections.push_back (_session->RouteGroupChanged.connect (sigc::mem_fun (*this, &GroupTabs::set_dirty)));
+	if (_session) {
+		_session_connections.add_connection (_session->RouteGroupChanged.connect (boost::bind (&GroupTabs::set_dirty, this)));
+	}
 }
 
 
diff --git a/gtk2_ardour/group_tabs.h b/gtk2_ardour/group_tabs.h
index bb764a02a5..dbe3174f1b 100644
--- a/gtk2_ardour/group_tabs.h
+++ b/gtk2_ardour/group_tabs.h
@@ -36,7 +36,7 @@ class GroupTabs : public CairoWidget, public EditorComponent
 public:
 	GroupTabs (Editor *);
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 protected:
 
diff --git a/gtk2_ardour/imageframe_socket_handler.cc b/gtk2_ardour/imageframe_socket_handler.cc
index 3d85eda5d4..dc9188db1b 100644
--- a/gtk2_ardour/imageframe_socket_handler.cc
+++ b/gtk2_ardour/imageframe_socket_handler.cc
@@ -1617,7 +1617,7 @@ ImageFrameSocketHandler::handle_rename_marker_view(const char* msg)
 void
 ImageFrameSocketHandler::handle_session_name_request(const char* msg)
 {
-	ARDOUR::Session* currentSession = thePublicEditor.current_session() ;
+	ARDOUR::Session* currentSession = thePublicEditor.session() ;
 
 	if(currentSession == 0)
 	{
diff --git a/gtk2_ardour/imageframe_time_axis.cc b/gtk2_ardour/imageframe_time_axis.cc
index 91a4b768fd..9e1eef2b2e 100644
--- a/gtk2_ardour/imageframe_time_axis.cc
+++ b/gtk2_ardour/imageframe_time_axis.cc
@@ -57,7 +57,7 @@ using namespace Gtk;
  * @param sess the current session
  * @param canvas the parent canvas item
  */
-ImageFrameTimeAxis::ImageFrameTimeAxis(const string & track_id, PublicEditor& ed, ARDOUR::Session& sess, ArdourCanvas::Canvas& canvas)
+ImageFrameTimeAxis::ImageFrameTimeAxis(const string & track_id, PublicEditor& ed, ARDOUR::Session* sess, ArdourCanvas::Canvas& canvas)
 	: AxisView(sess),
 	  VisualTimeAxis(track_id, ed, sess, canvas)
 {
@@ -89,7 +89,7 @@ ImageFrameTimeAxis::ImageFrameTimeAxis(const string & track_id, PublicEditor& ed
  */
 ImageFrameTimeAxis::~ImageFrameTimeAxis ()
 {
-	 GoingAway() ; /* EMIT_SIGNAL */
+	 GoingAway ; /* EMIT_SIGNAL */
 
 	// Destroy all the marker views we may have associaited with this TimeAxis
 	for(MarkerTimeAxisList::iterator iter = marker_time_axis_list.begin(); iter != marker_time_axis_list.end(); ++iter)
@@ -322,7 +322,7 @@ ImageFrameTimeAxis::add_marker_time_axis(MarkerTimeAxis* marker_track, void* src
 	else
 	{
 		marker_time_axis_list.push_back(marker_track) ;
-		marker_track->GoingAway.connect(sigc::bind(sigc::mem_fun(*this, &ImageFrameTimeAxis::remove_time_axis_view), marker_track, (void*)this));
+		scoped_connect (marker_track->GoingAway, boost::bind (&ImageFrameTimeAxis::remove_time_axis_view, this, marker_track, (void*)this));
 
 		 MarkerTimeAxisAdded(marker_track, src) ; /* EMIT_SIGNAL */
 		ret = true ;
diff --git a/gtk2_ardour/imageframe_time_axis.h b/gtk2_ardour/imageframe_time_axis.h
index 21db88e3e4..6b2576fe96 100644
--- a/gtk2_ardour/imageframe_time_axis.h
+++ b/gtk2_ardour/imageframe_time_axis.h
@@ -62,7 +62,7 @@ class ImageFrameTimeAxis : public VisualTimeAxis
 		 * @param sess the current session
 		 * @param canvas the parent canvas item
 		 */
-		ImageFrameTimeAxis(const std::string & track_id, PublicEditor& ed, ARDOUR::Session& sess, ArdourCanvas::Canvas& canvas) ;
+		ImageFrameTimeAxis(const std::string & track_id, PublicEditor& ed, ARDOUR::Session* sess, ArdourCanvas::Canvas& canvas) ;
 
 		/**
 		 * Destructor
diff --git a/gtk2_ardour/imageframe_time_axis_group.cc b/gtk2_ardour/imageframe_time_axis_group.cc
index c3599d1b00..28d2aac1a1 100644
--- a/gtk2_ardour/imageframe_time_axis_group.cc
+++ b/gtk2_ardour/imageframe_time_axis_group.cc
@@ -74,7 +74,7 @@ ImageFrameTimeAxisGroup::~ImageFrameTimeAxisGroup()
 		iter = next ;
 	}
 
-	 GoingAway() ; /* EMIT_SIGNAL */
+	 GoingAway ; /* EMIT_SIGNAL */
 }
 
 
@@ -216,7 +216,7 @@ ImageFrameTimeAxisGroup::add_imageframe_item(const string & frame_id, nframes_t
 
 		imageframe_views.push_front(ifv) ;
 
-		ifv->GoingAway.connect(sigc::bind(sigc::mem_fun(*this,&ImageFrameTimeAxisGroup::remove_imageframe_item), (void*)this)) ;
+		scoped_connect (ifv->GoingAway, boost::bind (&ImageFrameTimeAxisGroup::remove_imageframe_item, this, (void*)this));
 
 		 ImageFrameAdded(ifv, src) ; /* EMIT_SIGNAL */
 	}
diff --git a/gtk2_ardour/imageframe_time_axis_view.cc b/gtk2_ardour/imageframe_time_axis_view.cc
index 88cdbd53cc..fa339b42ec 100644
--- a/gtk2_ardour/imageframe_time_axis_view.cc
+++ b/gtk2_ardour/imageframe_time_axis_view.cc
@@ -214,7 +214,7 @@ ImageFrameTimeAxisView::add_imageframe_group(std::string group_id, void* src)
 
 		imageframe_groups.push_front(iftag) ;
 
-		iftag->GoingAway.connect(sigc::bind(sigc::mem_fun(*this,&ImageFrameTimeAxisView::remove_imageframe_group), iftag, (void*)this)) ;
+		scoped_connect (iftag->GoingAway, boost::bind (&ImageFrameTimeAxisView::remove_imageframe_group, this, iftag, (void*)this)) ;
 
 		 ImageFrameGroupAdded(iftag, src) ; /* EMIT_SIGNAL */
 	}
@@ -410,7 +410,7 @@ ImageFrameTimeAxisView::set_imageframe_duration_sec(double sec)
 {
 	if(selected_imageframe_group && selected_imageframe_view)
 	{
-		selected_imageframe_view->set_duration((nframes_t) (sec * _trackview.editor.current_session()->frame_rate()), this) ;
+		selected_imageframe_view->set_duration((nframes_t) (sec * _trackview.editor.session()->frame_rate()), this) ;
 	}
 }
 
diff --git a/gtk2_ardour/imageframe_view.cc b/gtk2_ardour/imageframe_view.cc
index 65d091804a..c704eb9768 100644
--- a/gtk2_ardour/imageframe_view.cc
+++ b/gtk2_ardour/imageframe_view.cc
@@ -287,7 +287,7 @@ ImageFrameView::add_marker_view_item(MarkerView* item, void* src)
 {
 	marker_view_list.push_back(item) ;
 
-	item->GoingAway.connect(sigc::bind(sigc::mem_fun(*this, &ImageFrameView::remove_marker_view_item), (void*)this));
+	scoped_connect (item->GoingAway, boost::bind (&ImageFrameView::remove_marker_view_item, this, (void*)this));
 
 	 MarkerViewAdded(item, src) ; /* EMIT_SIGNAL */
 }
diff --git a/gtk2_ardour/io_selector.h b/gtk2_ardour/io_selector.h
index f61d2cc5c2..63e02a2a75 100644
--- a/gtk2_ardour/io_selector.h
+++ b/gtk2_ardour/io_selector.h
@@ -122,7 +122,7 @@ class PortInsertWindow : public ArdourDialog
 	void accept ();
 
 	void plugin_going_away ();
-	sigc::connection going_away_connection;
+	boost::signals2::scoped_connection going_away_connection;
 
 	bool wm_delete (GdkEventAny*);
 };
diff --git a/gtk2_ardour/level_meter.cc b/gtk2_ardour/level_meter.cc
index 3ddc9d2f94..bd85596a8c 100644
--- a/gtk2_ardour/level_meter.cc
+++ b/gtk2_ardour/level_meter.cc
@@ -53,11 +53,11 @@ using namespace std;
 //sigc::signal<void,RouteGroup*> LevelMeter::ResetGroupPeakDisplays;
 
 
-LevelMeter::LevelMeter (Session& s)
-	: _session (s)
-	, _meter (0)
+LevelMeter::LevelMeter (Session* s)
+	: _meter (0)
 	, meter_length (0)
 {
+	set_session (s);
 	set_spacing (1);
 	Config->ParameterChanged.connect (sigc::mem_fun (*this, &LevelMeter::parameter_changed));
 	UI::instance()->theme_changed.connect (sigc::mem_fun(*this, &LevelMeter::on_theme_changed));
@@ -83,9 +83,9 @@ LevelMeter::set_meter (PeakMeter* meter)
 {
 	_configuration_connection.disconnect();
 	_meter = meter;
+
 	if (_meter) {
-		_configuration_connection = _meter->ConfigurationChanged.connect(
-			sigc::mem_fun(*this, &LevelMeter::configuration_changed));
+		_configuration_connection = _meter->ConfigurationChanged.connect(boost::bind (&LevelMeter::configuration_changed, this, _1, _2));
 	}
 }
 
diff --git a/gtk2_ardour/level_meter.h b/gtk2_ardour/level_meter.h
index bf0e081cce..cd2ccb7d7d 100644
--- a/gtk2_ardour/level_meter.h
+++ b/gtk2_ardour/level_meter.h
@@ -31,6 +31,7 @@
 #include <gtkmm/drawingarea.h>
 
 #include "ardour/types.h"
+#include "ardour/session_handle.h"
 
 #include <gtkmm2ext/click_box.h>
 #include <gtkmm2ext/focus_entry.h>
@@ -49,10 +50,10 @@ namespace Gtk {
 	class Menu;
 }
 
-class LevelMeter : public Gtk::HBox
+class LevelMeter : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   public:
-	LevelMeter (ARDOUR::Session&);
+	LevelMeter (ARDOUR::Session*);
 	~LevelMeter ();
 
 	virtual void set_meter (ARDOUR::PeakMeter* meter);
@@ -66,7 +67,6 @@ class LevelMeter : public Gtk::HBox
 	void setup_meters (int len=0, int width=3);
 
   private:
-	ARDOUR::Session&   _session;
 	ARDOUR::PeakMeter* _meter;
 
 	Width _width;
@@ -91,7 +91,7 @@ class LevelMeter : public Gtk::HBox
 	std::vector<MeterInfo> meters;
 	float                  max_peak;
 
-	sigc::connection _configuration_connection;
+	boost::signals2::scoped_connection _configuration_connection;
 
 	void hide_all_meters ();
 	gint meter_button_release (GdkEventButton*, uint32_t);
diff --git a/gtk2_ardour/location_ui.cc b/gtk2_ardour/location_ui.cc
index 4190a2c463..328d87b544 100644
--- a/gtk2_ardour/location_ui.cc
+++ b/gtk2_ardour/location_ui.cc
@@ -44,7 +44,8 @@ using namespace Gtk;
 using namespace Gtkmm2ext;
 
 LocationEditRow::LocationEditRow(Session * sess, Location * loc, int32_t num)
-	: location(0), session(0),
+	: SessionHandlePtr (0), /* explicitly set below */
+	  location(0), 
 	  item_table (1, 6, false),
 	  start_clock (X_("locationstart"), true, X_("LocationEditRowClock"), true, false),
 	  end_clock (X_("locationend"), true, X_("LocationEditRowClock"), true, false),
@@ -149,24 +150,22 @@ LocationEditRow::LocationEditRow(Session * sess, Location * loc, int32_t num)
 LocationEditRow::~LocationEditRow()
 {
 	if (location) {
- 		start_changed_connection.disconnect();
- 		end_changed_connection.disconnect();
- 		name_changed_connection.disconnect();
- 		changed_connection.disconnect();
- 		flags_changed_connection.disconnect();
+		connections.drop_connections ();
 	}
 }
 
 void
 LocationEditRow::set_session (Session *sess)
 {
-	session = sess;
+	SessionHandlePtr::set_session (sess);
 
-	if (!session) return;
+	if (!_session) { 
+		return;
+	}
 
-	start_clock.set_session (session);
-	end_clock.set_session (session);
-	length_clock.set_session (session);
+	start_clock.set_session (_session);
+	end_clock.set_session (_session);
+	length_clock.set_session (_session);
 
 }
 
@@ -184,11 +183,7 @@ void
 LocationEditRow::set_location (Location *loc)
 {
 	if (location) {
-		start_changed_connection.disconnect();
-		end_changed_connection.disconnect();
-		name_changed_connection.disconnect();
-		changed_connection.disconnect();
-		flags_changed_connection.disconnect();
+		connections.drop_connections ();
 	}
 
 	location = loc;
@@ -238,7 +233,7 @@ LocationEditRow::set_location (Location *loc)
 		cd_check_button.set_active (location->is_cd_marker());
 		cd_check_button.show();
 
-		if (location->start() == session->current_start_frame()) {
+		if (location->start() == _session->current_start_frame()) {
 			cd_check_button.set_sensitive (false);
 		} else {
 			cd_check_button.set_sensitive (true);
@@ -287,11 +282,11 @@ LocationEditRow::set_location (Location *loc)
 	end_clock.set_sensitive (!location->locked());
 	length_clock.set_sensitive (!location->locked());
 
-	start_changed_connection = location->start_changed.connect (sigc::mem_fun(*this, &LocationEditRow::start_changed));
-	end_changed_connection = location->end_changed.connect (sigc::mem_fun(*this, &LocationEditRow::end_changed));
-	name_changed_connection = location->name_changed.connect (sigc::mem_fun(*this, &LocationEditRow::name_changed));
-	changed_connection = location->changed.connect (sigc::mem_fun(*this, &LocationEditRow::location_changed));
-	flags_changed_connection = location->FlagsChanged.connect (sigc::mem_fun(*this, &LocationEditRow::flags_changed));
+	connections.add_connection (location->start_changed.connect (boost::bind (&LocationEditRow::start_changed, this, _1)));
+	connections.add_connection (location->end_changed.connect (boost::bind (&LocationEditRow::end_changed, this, _1)));
+	connections.add_connection (location->name_changed.connect (boost::bind (&LocationEditRow::name_changed, this, _1)));
+	connections.add_connection (location->changed.connect (boost::bind (&LocationEditRow::location_changed, this, _1)));
+	connections.add_connection (location->FlagsChanged.connect (boost::bind (&LocationEditRow::flags_changed, this, _1, _2)));
 }
 
 void
@@ -406,7 +401,7 @@ LocationEditRow::cd_toggled ()
 	//}
 
 	if (cd_check_button.get_active()) {
-		if (location->start() <= session->current_start_frame()) {
+		if (location->start() <= _session->current_start_frame()) {
 			error << _("You cannot put a CD marker at the start of the session") << endmsg;
 			cd_check_button.set_active (false);
 			return;
@@ -518,7 +513,7 @@ LocationEditRow::start_changed (ARDOUR::Location *loc)
 
 	start_clock.set (location->start());
 
-	if (location->start() == session->current_start_frame()) {
+	if (location->start() == _session->current_start_frame()) {
 		cd_check_button.set_sensitive (false);
 	} else {
 		cd_check_button.set_sensitive (true);
@@ -587,8 +582,7 @@ LocationEditRow::focus_name() {
 
 
 LocationUI::LocationUI ()
-	: session (0)
-	, add_location_button (_("New Marker"))
+	: add_location_button (_("New Marker"))
 	, add_range_button (_("New Range"))
 {
 	i_am_the_modifier = 0;
@@ -681,12 +675,12 @@ LocationUI::do_location_remove (ARDOUR::Location *loc)
 		return FALSE;
 	}
 
-	session->begin_reversible_command (_("remove marker"));
-	XMLNode &before = session->locations()->get_state();
-	session->locations()->remove (loc);
-	XMLNode &after = session->locations()->get_state();
-	session->add_command(new MementoCommand<Locations>(*(session->locations()), &before, &after));
-	session->commit_reversible_command ();
+	_session->begin_reversible_command (_("remove marker"));
+	XMLNode &before = _session->locations()->get_state();
+	_session->locations()->remove (loc);
+	XMLNode &after = _session->locations()->get_state();
+	_session->add_command(new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+	_session->commit_reversible_command ();
 
 	return FALSE;
 }
@@ -769,7 +763,7 @@ LocationUI::map_locations (Locations::LocationList& locations)
 
 		if (location->is_mark()) {
 			mark_n++;
-			erow = manage (new LocationEditRow(session, location, mark_n));
+			erow = manage (new LocationEditRow(_session, location, mark_n));
 			erow->remove_requested.connect (sigc::mem_fun(*this, &LocationUI::location_remove_requested));
  			erow->redraw_ranges.connect (sigc::mem_fun(*this, &LocationUI::location_redraw_ranges));
 			loc_children.push_back(Box_Helpers::Element(*erow, PACK_SHRINK, 1, PACK_START));
@@ -779,17 +773,17 @@ LocationUI::map_locations (Locations::LocationList& locations)
 			}
 		}
 		else if (location->is_auto_punch()) {
-			punch_edit_row.set_session (session);
+			punch_edit_row.set_session (_session);
 			punch_edit_row.set_location (location);
 			punch_edit_row.show_all();
 		}
 		else if (location->is_auto_loop()) {
-			loop_edit_row.set_session (session);
+			loop_edit_row.set_session (_session);
 			loop_edit_row.set_location (location);
 			loop_edit_row.show_all();
 		}
 		else {
-			erow = manage (new LocationEditRow(session, location));
+			erow = manage (new LocationEditRow(_session, location));
 			erow->remove_requested.connect (sigc::mem_fun(*this, &LocationUI::location_remove_requested));
 			range_children.push_back(Box_Helpers::Element(*erow,  PACK_SHRINK, 1, PACK_START));
 		}
@@ -804,19 +798,19 @@ LocationUI::add_new_location()
 {
 	string markername;
 
-	if (session) {
-		nframes_t where = session->audible_frame();
-		session->locations()->next_available_name(markername,"mark");
+	if (_session) {
+		nframes_t where = _session->audible_frame();
+		_session->locations()->next_available_name(markername,"mark");
 		Location *location = new Location (where, where, markername, Location::IsMark);
 		if (Config->get_name_new_markers()) {
 			newest_location = location;
 		}
-		session->begin_reversible_command (_("add marker"));
-		XMLNode &before = session->locations()->get_state();
-		session->locations()->add (location, true);
-		XMLNode &after = session->locations()->get_state();
-		session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-		session->commit_reversible_command ();
+		_session->begin_reversible_command (_("add marker"));
+		XMLNode &before = _session->locations()->get_state();
+		_session->locations()->add (location, true);
+		XMLNode &after = _session->locations()->get_state();
+		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+		_session->commit_reversible_command ();
 	}
 
 }
@@ -826,28 +820,19 @@ LocationUI::add_new_range()
 {
 	string rangename;
 
-	if (session) {
-		nframes_t where = session->audible_frame();
-		session->locations()->next_available_name(rangename,"unnamed");
+	if (_session) {
+		nframes_t where = _session->audible_frame();
+		_session->locations()->next_available_name(rangename,"unnamed");
 		Location *location = new Location (where, where, rangename, Location::IsRangeMarker);
-		session->begin_reversible_command (_("add range marker"));
-		XMLNode &before = session->locations()->get_state();
-		session->locations()->add (location, true);
-		XMLNode &after = session->locations()->get_state();
-		session->add_command (new MementoCommand<Locations>(*(session->locations()), &before, &after));
-		session->commit_reversible_command ();
+		_session->begin_reversible_command (_("add range marker"));
+		XMLNode &before = _session->locations()->get_state();
+		_session->locations()->add (location, true);
+		XMLNode &after = _session->locations()->get_state();
+		_session->add_command (new MementoCommand<Locations>(*(_session->locations()), &before, &after));
+		_session->commit_reversible_command ();
 	}
 }
 
-
-void
-LocationUI::refresh_location_list_s (Change ignored)
-{
-	ENSURE_GUI_THREAD (*this, &LocationUI::refresh_location_list_s, ignored)
-
-	refresh_location_list ();
-}
-
 void
 LocationUI::refresh_location_list ()
 {
@@ -863,8 +848,8 @@ LocationUI::refresh_location_list ()
 	loc_children.clear();
 	range_children.clear();
 
-	if (session) {
-		session->locations()->apply (*this, &LocationUI::map_locations);
+	if (_session) {
+		_session->locations()->apply (*this, &LocationUI::map_locations);
 	}
 
 }
@@ -872,22 +857,22 @@ LocationUI::refresh_location_list ()
 void
 LocationUI::set_session(ARDOUR::Session* s)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
 
-	if (session) {
-		session->locations()->changed.connect (sigc::mem_fun(*this, &LocationUI::refresh_location_list));
-		session->locations()->StateChanged.connect (sigc::mem_fun(*this, &LocationUI::refresh_location_list_s));
-		session->locations()->added.connect (sigc::mem_fun(*this, &LocationUI::location_added));
-		session->locations()->removed.connect (sigc::mem_fun(*this, &LocationUI::location_removed));
-		session->GoingAway.connect (sigc::mem_fun(*this, &LocationUI::session_gone));
+	if (_session) {
+		_session_connections.add_connection (_session->locations()->changed.connect (boost::bind (&LocationUI::refresh_location_list, this)));
+		_session_connections.add_connection (_session->locations()->StateChanged.connect (boost::bind (&LocationUI::refresh_location_list, this)));
+		_session_connections.add_connection (_session->locations()->added.connect (boost::bind (&LocationUI::location_added, this, _1)));
+		_session_connections.add_connection (_session->locations()->removed.connect (boost::bind (&LocationUI::location_removed, this, _1)));
 	}
+
 	refresh_location_list ();
 }
 
 void
-LocationUI::session_gone()
+LocationUI::session_going_away()
 {
-	ENSURE_GUI_THREAD (*this, &LocationUI::session_gone)
+	ENSURE_GUI_THREAD (*this, &LocationUI::session_going_away);
 
 	using namespace Box_Helpers;
 	BoxList & loc_children = location_rows.children();
@@ -901,6 +886,8 @@ LocationUI::session_gone()
 
 	punch_edit_row.set_session (0);
 	punch_edit_row.set_location (0);
+
+	SessionHandlePtr::session_going_away ();
 }
 
 /*------------------------*/
@@ -938,13 +925,11 @@ LocationUIWindow::set_session (Session *s)
 {
 	ArdourDialog::set_session (s);
 	_ui.set_session (s);
-
-	s->GoingAway.connect (sigc::mem_fun (*this, &LocationUIWindow::session_gone));
 }
 
 void
-LocationUIWindow::session_gone ()
+LocationUIWindow::session_going_away ()
 {
+	ArdourDialog::session_going_away ();
 	hide_all();
-	ArdourDialog::session_gone ();
 }
diff --git a/gtk2_ardour/location_ui.h b/gtk2_ardour/location_ui.h
index 56401f6139..dd735cddba 100644
--- a/gtk2_ardour/location_ui.h
+++ b/gtk2_ardour/location_ui.h
@@ -29,18 +29,20 @@
 #include <gtkmm/paned.h>
 #include <gtkmm/scrolledwindow.h>
 
+#include "pbd/scoped_connections.h"
+
 #include "ardour/location.h"
+#include "ardour/session_handle.h"
 
 #include "ardour_dialog.h"
 #include "audio_clock.h"
 
 namespace ARDOUR {
 	class LocationStack;
-	class Session;
 	class Location;
 }
 
-class LocationEditRow  : public Gtk::HBox
+class LocationEditRow  : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   public:
 	LocationEditRow (ARDOUR::Session *sess=0, ARDOUR::Location *loc=0, int32_t num=-1);
@@ -66,9 +68,6 @@ class LocationEditRow  : public Gtk::HBox
 	};
 
 	ARDOUR::Location *location;
-	ARDOUR::Session  *session;
-
-
 
 	Gtk::Table    item_table;
 
@@ -102,7 +101,6 @@ class LocationEditRow  : public Gtk::HBox
 	Gtk::CheckButton   scms_check_button;
 	Gtk::CheckButton   preemph_check_button;
 
-
 	guint32 i_am_the_modifier;
 	int   number;
 
@@ -130,34 +128,27 @@ class LocationEditRow  : public Gtk::HBox
 	void location_changed (ARDOUR::Location *);
 	void flags_changed (ARDOUR::Location *, void *src);
 
-	sigc::connection start_changed_connection;
-	sigc::connection end_changed_connection;
-	sigc::connection name_changed_connection;
-	sigc::connection changed_connection;
-	sigc::connection flags_changed_connection;
-
+	PBD::ScopedConnectionList connections;
 };
 
-class LocationUI : public Gtk::HBox
+class LocationUI : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   public:
 	LocationUI ();
 	~LocationUI ();
 	
-	virtual void set_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	void add_new_location();
 	void add_new_range();
 
 	void refresh_location_list ();
-	void refresh_location_list_s (ARDOUR::Change);
 
   private:
-	ARDOUR::Session* session;
 	ARDOUR::LocationStack* locations;
 	ARDOUR::Location *newest_location;
 
-	void session_gone();
+	void session_going_away ();
 
 	Gtk::VBox  location_vpacker;
 
@@ -212,7 +203,7 @@ class LocationUIWindow : public ArdourDialog
   protected:
 	LocationUI _ui;
 	bool on_delete_event (GdkEventAny*);
-	void session_gone();
+	void session_going_away();
 };
 
 #endif // __ardour_location_ui_h__
diff --git a/gtk2_ardour/marker_time_axis.cc b/gtk2_ardour/marker_time_axis.cc
index 9dea703dfd..c58f607be6 100644
--- a/gtk2_ardour/marker_time_axis.cc
+++ b/gtk2_ardour/marker_time_axis.cc
@@ -56,7 +56,7 @@ using namespace Gtk;
  * @param name the name/id of this time axis
  * @param tav the associated track view that this MarkerTimeAxis is marking up
  */
-MarkerTimeAxis::MarkerTimeAxis (PublicEditor& ed, ARDOUR::Session& sess, Canvas& canvas, const string & name, TimeAxisView* tav)
+MarkerTimeAxis::MarkerTimeAxis (PublicEditor& ed, ARDOUR::Session* sess, Canvas& canvas, const string & name, TimeAxisView* tav)
 	: AxisView(sess),
 	  VisualTimeAxis(name, ed, sess, canvas)
 {
@@ -90,7 +90,7 @@ MarkerTimeAxis::MarkerTimeAxis (PublicEditor& ed, ARDOUR::Session& sess, Canvas&
  */
 MarkerTimeAxis::~MarkerTimeAxis()
 {
-	GoingAway() ; /* EMIT_SIGNAL */
+	GoingAway ; /* EMIT_SIGNAL */
 
 	// destroy the view helper
 	// this handles removing and destroying individual marker items
diff --git a/gtk2_ardour/marker_time_axis.h b/gtk2_ardour/marker_time_axis.h
index 05b95bddaa..67c3e2beff 100644
--- a/gtk2_ardour/marker_time_axis.h
+++ b/gtk2_ardour/marker_time_axis.h
@@ -65,7 +65,7 @@ class MarkerTimeAxis : public VisualTimeAxis
 		 * @param name the name/id of this time axis
 		 * @param tav the associated track view that this MarkerTimeAxis is marking up
 		 */
-		MarkerTimeAxis(PublicEditor& ed, ARDOUR::Session& sess, ArdourCanvas::Canvas& canvas, const std::string & name, TimeAxisView* tav) ;
+		MarkerTimeAxis(PublicEditor& ed, ARDOUR::Session* sess, ArdourCanvas::Canvas& canvas, const std::string & name, TimeAxisView* tav) ;
 
 		/**
 		 * Destructor
diff --git a/gtk2_ardour/marker_time_axis_view.cc b/gtk2_ardour/marker_time_axis_view.cc
index 4189788b4c..402f2ac479 100644
--- a/gtk2_ardour/marker_time_axis_view.cc
+++ b/gtk2_ardour/marker_time_axis_view.cc
@@ -211,7 +211,7 @@ MarkerTimeAxisView::add_marker_view(ImageFrameView* ifv, std::string mark_type,
 	ifv->add_marker_view_item(mv, src) ;
 	marker_view_list.push_front(mv) ;
 
-	mv->GoingAway.connect(sigc::bind (sigc::mem_fun(*this,&MarkerTimeAxisView::remove_marker_view), (void*)this)) ;
+	scoped_connect (mv->GoingAway, boost::bind (&MarkerTimeAxisView::remove_marker_view, this, (void*)this));
 
 	 MarkerViewAdded(mv,src) ; /* EMIT_SIGNAL */
 
@@ -337,7 +337,7 @@ MarkerTimeAxisView::set_marker_duration_sec(double sec)
 {
   if(get_selected_time_axis_item() != 0)
   {
-	  get_selected_time_axis_item()->set_duration((nframes_t) (sec * _trackview.editor.current_session()->frame_rate()), this) ;
+	  get_selected_time_axis_item()->set_duration((nframes_t) (sec * _trackview.editor.session()->frame_rate()), this) ;
   }
 }
 
diff --git a/gtk2_ardour/midi_cut_buffer.cc b/gtk2_ardour/midi_cut_buffer.cc
index 008597bc84..9c1c84ede4 100644
--- a/gtk2_ardour/midi_cut_buffer.cc
+++ b/gtk2_ardour/midi_cut_buffer.cc
@@ -20,11 +20,11 @@
 
 using namespace ARDOUR;
 
-MidiCutBuffer::MidiCutBuffer (Session& s)
-	: AutomatableSequence<MidiModel::TimeType> (s, 0)
+MidiCutBuffer::MidiCutBuffer (Session* s)
+	: AutomatableSequence<MidiModel::TimeType> (*s, 0)
 	, _origin (0)
 {
-
+	
 }
 
 MidiCutBuffer::~MidiCutBuffer ()
diff --git a/gtk2_ardour/midi_cut_buffer.h b/gtk2_ardour/midi_cut_buffer.h
index 4281b962bc..a52771019d 100644
--- a/gtk2_ardour/midi_cut_buffer.h
+++ b/gtk2_ardour/midi_cut_buffer.h
@@ -30,7 +30,7 @@ class MidiCutBuffer : public ARDOUR::AutomatableSequence<ARDOUR::MidiModel::Time
   public:
 	typedef ARDOUR::MidiModel::TimeType TimeType;
 
-	MidiCutBuffer (ARDOUR::Session&);
+	MidiCutBuffer (ARDOUR::Session*);
 	~MidiCutBuffer();
 
 	TimeType origin() const { return _origin; }
diff --git a/gtk2_ardour/midi_list_editor.cc b/gtk2_ardour/midi_list_editor.cc
index b807de28f9..026b09b927 100644
--- a/gtk2_ardour/midi_list_editor.cc
+++ b/gtk2_ardour/midi_list_editor.cc
@@ -31,11 +31,12 @@ using namespace Gtk;
 using namespace Glib;
 using namespace ARDOUR;
 
-MidiListEditor::MidiListEditor (Session& s, boost::shared_ptr<MidiRegion> r)
+MidiListEditor::MidiListEditor (Session* s, boost::shared_ptr<MidiRegion> r)
 	: ArdourDialog (r->name(), false, false)
-	, session (s)
 	, region (r)
 {
+	set_session (s);
+
 	model = ListStore::create (columns);
 	view.set_model (model);
 
@@ -96,40 +97,43 @@ MidiListEditor::redisplay_model ()
 	view.set_model (Glib::RefPtr<Gtk::ListStore>(0));
 	model->clear ();
 
-	MidiModel::Notes notes = region->midi_source(0)->model()->notes();
-	TreeModel::Row row;
-
-	for (MidiModel::Notes::iterator i = notes.begin(); i != notes.end(); ++i) {
-		row = *(model->append());
-		row[columns.channel] = (*i)->channel();
-		row[columns.note_name] = _("Note");
-		row[columns.note] = (*i)->note();
-		row[columns.velocity] = (*i)->velocity();
-
-		BBT_Time bbt;
-		BBT_Time dur;
-		stringstream ss;
-
-		session.tempo_map().bbt_time (region->position(), bbt);
-
-		dur.bars = 0;
-		dur.beats = floor ((*i)->time());
-		dur.ticks = 0;
-
-		session.tempo_map().bbt_duration_at (region->position(), dur, 0);
-
-		ss << bbt;
-		row[columns.start] = ss.str();
-		ss << dur;
-		row[columns.length] = ss.str();
-
-		session.tempo_map().bbt_time (region->position(), bbt);
-		/* XXX get end point */
-
-		ss << bbt;
-		row[columns.end] = ss.str();
-
-		row[columns._note] = (*i);
+	if (_session) {
+		
+		MidiModel::Notes notes = region->midi_source(0)->model()->notes();
+		TreeModel::Row row;
+		
+		for (MidiModel::Notes::iterator i = notes.begin(); i != notes.end(); ++i) {
+			row = *(model->append());
+			row[columns.channel] = (*i)->channel();
+			row[columns.note_name] = _("Note");
+			row[columns.note] = (*i)->note();
+			row[columns.velocity] = (*i)->velocity();
+			
+			BBT_Time bbt;
+			BBT_Time dur;
+			stringstream ss;
+			
+			_session->tempo_map().bbt_time (region->position(), bbt);
+			
+			dur.bars = 0;
+			dur.beats = floor ((*i)->time());
+			dur.ticks = 0;
+			
+			_session->tempo_map().bbt_duration_at (region->position(), dur, 0);
+			
+			ss << bbt;
+			row[columns.start] = ss.str();
+			ss << dur;
+			row[columns.length] = ss.str();
+			
+			_session->tempo_map().bbt_time (region->position(), bbt);
+			/* XXX get end point */
+			
+			ss << bbt;
+			row[columns.end] = ss.str();
+			
+			row[columns._note] = (*i);
+		}
 	}
 
 	view.set_model (model);
diff --git a/gtk2_ardour/midi_list_editor.h b/gtk2_ardour/midi_list_editor.h
index 96a04ada7c..de7b2220bb 100644
--- a/gtk2_ardour/midi_list_editor.h
+++ b/gtk2_ardour/midi_list_editor.h
@@ -26,6 +26,8 @@
 
 #include "evoral/types.hpp"
 
+#include "ardour/session_handle.h"
+
 #include "ardour_dialog.h"
 
 namespace ARDOUR {
@@ -39,7 +41,7 @@ class MidiListEditor : public ArdourDialog
   public:
 	typedef Evoral::Note<Evoral::MusicalTime> NoteType;
 
-	MidiListEditor(ARDOUR::Session&, boost::shared_ptr<ARDOUR::MidiRegion>);
+	MidiListEditor(ARDOUR::Session*, boost::shared_ptr<ARDOUR::MidiRegion>);
 	~MidiListEditor();
 
   private:
@@ -64,7 +66,6 @@ class MidiListEditor : public ArdourDialog
 		Gtk::TreeModelColumn<boost::shared_ptr<NoteType> > _note;
 	};
 
-	ARDOUR::Session&             session;
 	MidiListModelColumns         columns;
 	Glib::RefPtr<Gtk::ListStore> model;
 	Gtk::TreeView                view;
diff --git a/gtk2_ardour/midi_region_view.cc b/gtk2_ardour/midi_region_view.cc
index a8f6f11b42..d2f1657821 100644
--- a/gtk2_ardour/midi_region_view.cc
+++ b/gtk2_ardour/midi_region_view.cc
@@ -552,7 +552,7 @@ MidiRegionView::create_note_at(double x, double y, double length)
 
 	MidiModel::DeltaCommand* cmd = _model->new_delta_command("add note");
 	cmd->add(new_note);
-	_model->apply_command(trackview.session(), cmd);
+	_model->apply_command(*trackview.session(), cmd);
 
 	play_midi_note (new_note);
 }
@@ -585,8 +585,8 @@ MidiRegionView::display_model(boost::shared_ptr<MidiModel> model)
 {
 	_model = model;
 	content_connection.disconnect ();
-	content_connection = _model->ContentsChanged.connect(
-			sigc::mem_fun(this, &MidiRegionView::redisplay_model));
+	content_connection = _model->ContentsChanged.connect (boost::bind (&MidiRegionView::redisplay_model, this));
+
 	clear_events ();
 
 	if (_enable_display) {
@@ -665,7 +665,7 @@ MidiRegionView::apply_delta()
 		_marked_for_selection.insert((*i)->note());
 	}
 
-	_model->apply_command(trackview.session(), _delta_command);
+	_model->apply_command(*trackview.session(), _delta_command);
 	_delta_command = 0;
 	midi_view()->midi_track()->diskstream()->playlist_modified();
 
@@ -680,7 +680,7 @@ MidiRegionView::apply_diff ()
 		return;
 	}
 
-	_model->apply_command(trackview.session(), _diff_command);
+	_model->apply_command(*trackview.session(), _diff_command);
 	_diff_command = 0;
 	midi_view()->midi_track()->diskstream()->playlist_modified();
 
@@ -699,7 +699,7 @@ MidiRegionView::apply_delta_as_subcommand()
 		_marked_for_selection.insert((*i)->note());
 	}
 
-	_model->apply_command_as_subcommand(trackview.session(), _delta_command);
+	_model->apply_command_as_subcommand(*trackview.session(), _delta_command);
 	_delta_command = 0;
 	midi_view()->midi_track()->diskstream()->playlist_modified();
 
@@ -719,7 +719,7 @@ MidiRegionView::apply_diff_as_subcommand()
 		_marked_for_selection.insert((*i)->note());
 	}
 
-	_model->apply_command_as_subcommand(trackview.session(), _diff_command);
+	_model->apply_command_as_subcommand(*trackview.session(), _diff_command);
 	_diff_command = 0;
 	midi_view()->midi_track()->diskstream()->playlist_modified();
 
@@ -1071,7 +1071,7 @@ MidiRegionView::add_ghost (TimeAxisView& tv)
 		}
 	}
 
-	ghost->GoingAway.connect (sigc::mem_fun(*this, &MidiRegionView::remove_ghost));
+	ghost->GoingAway.connect (boost::bind (&RegionView::remove_ghost, this, _1));
 
 	return ghost;
 }
@@ -1151,7 +1151,7 @@ MidiRegionView::play_midi_note(boost::shared_ptr<NoteType> note)
 
 	const double note_length_beats = (note->off_event().time() - note->on_event().time());
 	nframes_t note_length_ms = beats_to_frames(note_length_beats)
-			* (1000 / (double)route_ui->session().nominal_frame_rate());
+			* (1000 / (double)route_ui->session()->nominal_frame_rate());
 	Glib::signal_timeout().connect(sigc::bind(sigc::mem_fun(this, &MidiRegionView::play_midi_note_off), note),
 			note_length_ms, G_PRIORITY_DEFAULT);
 }
@@ -2431,11 +2431,11 @@ MidiRegionView::paste (nframes64_t pos, float times, const MidiCutBuffer& mcb)
 
 	if (end_frame > region_end) {
 
-		trackview.session().begin_reversible_command (_("paste"));
+		trackview.session()->begin_reversible_command (_("paste"));
 
 		XMLNode& before (_region->get_state());
 		_region->set_length (end_frame, this);
-		trackview.session().add_command (new MementoCommand<Region>(*_region, &before, &_region->get_state()));
+		trackview.session()->add_command (new MementoCommand<Region>(*_region, &before, &_region->get_state()));
 	}
 
 	apply_delta ();
diff --git a/gtk2_ardour/midi_region_view.h b/gtk2_ardour/midi_region_view.h
index 22c2b845fd..e8c25e8647 100644
--- a/gtk2_ardour/midi_region_view.h
+++ b/gtk2_ardour/midi_region_view.h
@@ -24,6 +24,9 @@
 
 #include <libgnomecanvasmm.h>
 #include <libgnomecanvasmm/polygon.h>
+
+#include <boost/signals2.hpp>
+
 #include "ardour/midi_track.h"
 #include "ardour/midi_region.h"
 #include "ardour/midi_model.h"
@@ -386,7 +389,7 @@ class MidiRegionView : public RegionView
 	std::vector<NoteResizeData *> _resize_data;
 
 	/* connection used to connect to model's ContentChanged signal */
-	sigc::connection content_connection;
+	boost::signals2::scoped_connection content_connection;
 
 	ArdourCanvas::CanvasNoteEvent* find_canvas_note (boost::shared_ptr<NoteType>);
 	Events::iterator _optimization_iterator;
diff --git a/gtk2_ardour/midi_streamview.cc b/gtk2_ardour/midi_streamview.cc
index 77d9afabae..4d0c7fa385 100644
--- a/gtk2_ardour/midi_streamview.cc
+++ b/gtk2_ardour/midi_streamview.cc
@@ -180,7 +180,7 @@ MidiStreamView::add_region_view_internal (boost::shared_ptr<Region> r, bool wfd,
 	display_region (region_view, wfd);
 
 	/* catch regionview going away */
-	region->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &MidiStreamView::remove_region_view), region));
+	scoped_connect (region->GoingAway, boost::bind (&MidiStreamView::remove_region_view, this, region));
 
 	RegionViewAdded (region_view);
 
@@ -383,10 +383,10 @@ MidiStreamView::setup_rec_box ()
 {
 	// cerr << _trackview.name() << " streamview SRB\n";
 
-	if (_trackview.session().transport_rolling()) {
+	if (_trackview.session()->transport_rolling()) {
 
 		if (!rec_active &&
-		    _trackview.session().record_status() == Session::Recording &&
+		    _trackview.session()->record_status() == Session::Recording &&
 		    _trackview.get_diskstream()->record_enabled()) {
 
 			if (use_rec_regions && rec_regions.size() == rec_rects.size()) {
@@ -395,19 +395,15 @@ MidiStreamView::setup_rec_box ()
 
 				MidiRegion::SourceList sources;
 
-				for (list<sigc::connection>::iterator prc = rec_data_ready_connections.begin();
-						prc != rec_data_ready_connections.end(); ++prc) {
-					(*prc).disconnect();
-				}
-				rec_data_ready_connections.clear();
+				rec_data_ready_connections.drop_connections ();
 
 				boost::shared_ptr<MidiDiskstream> mds = _trackview.midi_track()->midi_diskstream();
 
 				sources.push_back(mds->write_source());
 
-				rec_data_ready_connections.push_back (mds->write_source()->ViewDataRangeReady.connect (sigc::bind (
-						sigc::mem_fun (*this, &MidiStreamView::rec_data_range_ready),
-						boost::weak_ptr<Source>(mds->write_source()))));
+				rec_data_ready_connections.add_connection (mds->write_source()->ViewDataRangeReady.connect 
+									   (boost::bind (&MidiStreamView::rec_data_range_ready, this,
+											 _1, _2, boost::weak_ptr<Source>(mds->write_source()))));
 
 				// handle multi
 
@@ -422,7 +418,7 @@ MidiStreamView::setup_rec_box ()
 
 				assert(region);
 				region->block_property_changes ();
-				region->set_position (_trackview.session().transport_frame(), this);
+				region->set_position (_trackview.session()->transport_frame(), this);
 				rec_regions.push_back (make_pair(region, (RegionView*)0));
 
 				// rec regions are destroyed in setup_rec_box
@@ -455,7 +451,7 @@ MidiStreamView::setup_rec_box ()
 
 			RecBoxInfo recbox;
 			recbox.rectangle = rec_rect;
-			recbox.start = _trackview.session().transport_frame();
+			recbox.start = _trackview.session()->transport_frame();
 			recbox.length = 0;
 
 			rec_rects.push_back (recbox);
@@ -467,7 +463,7 @@ MidiStreamView::setup_rec_box ()
 			rec_active = true;
 
 		} else if (rec_active &&
-			   (_trackview.session().record_status() != Session::Recording ||
+			   (_trackview.session()->record_status() != Session::Recording ||
 			    !_trackview.get_diskstream()->record_enabled())) {
 			screen_update_connection.disconnect();
 			rec_active = false;
@@ -482,12 +478,7 @@ MidiStreamView::setup_rec_box ()
 
 			/* disconnect rapid update */
 			screen_update_connection.disconnect();
-
-			for (list<sigc::connection>::iterator prc = rec_data_ready_connections.begin();
-					prc != rec_data_ready_connections.end(); ++prc) {
-				(*prc).disconnect();
-			}
-			rec_data_ready_connections.clear();
+			rec_data_ready_connections.drop_connections ();
 
 			rec_updating = false;
 			rec_active = false;
@@ -575,7 +566,7 @@ MidiStreamView::update_rec_regions (boost::shared_ptr<MidiModel> data, nframes_t
 						gdouble xend = _trackview.editor().frame_to_pixel (region->position() + region->length());
 						rect->property_x2() = xend;
 
-						ARDOUR::BeatsFramesConverter tconv(_trackview.session().tempo_map(), region->position());
+						ARDOUR::BeatsFramesConverter tconv(_trackview.session()->tempo_map(), region->position());
 						const MidiModel::TimeType start_beats = tconv.from(start);
 
 						/* draw events */
diff --git a/gtk2_ardour/midi_time_axis.cc b/gtk2_ardour/midi_time_axis.cc
index c8c34e4369..9344e19943 100644
--- a/gtk2_ardour/midi_time_axis.cc
+++ b/gtk2_ardour/midi_time_axis.cc
@@ -93,7 +93,7 @@ using namespace Editing;
 static const uint32_t MIDI_CONTROLS_BOX_MIN_HEIGHT = 162;
 static const uint32_t KEYBOARD_MIN_HEIGHT = 140;
 
-MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session& sess,
+MidiTimeAxisView::MidiTimeAxisView (PublicEditor& ed, Session* sess,
 		boost::shared_ptr<Route> rt, Canvas& canvas)
 	: AxisView(sess) // virtually inherited
 	, RouteTimeAxisView(ed, sess, rt, canvas)
@@ -718,21 +718,21 @@ MidiTimeAxisView::add_region (nframes64_t pos)
 
 	nframes64_t start = pos;
 	real_editor->snap_to (start, -1);
-	const Meter& m = _session.tempo_map().meter_at(start);
-	const Tempo& t = _session.tempo_map().tempo_at(start);
-	double length = floor (m.frames_per_bar(t, _session.frame_rate()));
+	const Meter& m = _session->tempo_map().meter_at(start);
+	const Tempo& t = _session->tempo_map().tempo_at(start);
+	double length = floor (m.frames_per_bar(t, _session->frame_rate()));
 
 	const boost::shared_ptr<MidiDiskstream> diskstream =
 		boost::dynamic_pointer_cast<MidiDiskstream>(view()->trackview().track()->diskstream());
 
-	boost::shared_ptr<Source> src = _session.create_midi_source_for_session (*diskstream.get());
+	boost::shared_ptr<Source> src = _session->create_midi_source_for_session (*diskstream.get());
 
 	boost::shared_ptr<Region> region = (RegionFactory::create (src, 0, (nframes_t) length,
 								   PBD::basename_nosuffix(src->name())));
 
 	playlist()->add_region (region, start);
 	XMLNode &after = playlist()->get_state();
-	_session.add_command (new MementoCommand<Playlist> (*playlist().get(), &before, &after));
+	_session->add_command (new MementoCommand<Playlist> (*playlist().get(), &before, &after));
 
 	real_editor->commit_reversible_command();
 
diff --git a/gtk2_ardour/midi_time_axis.h b/gtk2_ardour/midi_time_axis.h
index 85dcd2b9ea..a24ae43f10 100644
--- a/gtk2_ardour/midi_time_axis.h
+++ b/gtk2_ardour/midi_time_axis.h
@@ -57,7 +57,7 @@ class PianoRollHeader;
 class MidiTimeAxisView : public RouteTimeAxisView
 {
   public:
- 	MidiTimeAxisView (PublicEditor&, ARDOUR::Session&, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
+ 	MidiTimeAxisView (PublicEditor&, ARDOUR::Session*, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
  	virtual ~MidiTimeAxisView ();
 
 	MidiStreamView* midi_view();
diff --git a/gtk2_ardour/mixer_strip.cc b/gtk2_ardour/mixer_strip.cc
index 01f67c51fe..bfbdb6ac6e 100644
--- a/gtk2_ardour/mixer_strip.cc
+++ b/gtk2_ardour/mixer_strip.cc
@@ -73,12 +73,12 @@ sigc::signal<void,boost::shared_ptr<Route> > MixerStrip::SwitchIO;
 
 int MixerStrip::scrollbar_height = 0;
 
-MixerStrip::MixerStrip (Mixer_UI& mx, Session& sess, bool in_mixer)
+MixerStrip::MixerStrip (Mixer_UI& mx, Session* sess, bool in_mixer)
 	: AxisView(sess)
 	, RouteUI (sess)
 	,_mixer(mx)
 	, _mixer_owned (in_mixer)
-	, processor_box (sess, sigc::mem_fun(*this, &MixerStrip::plugin_selector), mx.selection(), this, in_mixer)
+	, processor_box (sess, boost::bind (&MixerStrip::plugin_selector, this), mx.selection(), this, in_mixer)
 	, gpm (sess, 250)
 	, panners (sess)
 	, _mono_button (_("Mono"))
@@ -99,7 +99,7 @@ MixerStrip::MixerStrip (Mixer_UI& mx, Session& sess, bool in_mixer)
 	}
 }
 
-MixerStrip::MixerStrip (Mixer_UI& mx, Session& sess, boost::shared_ptr<Route> rt, bool in_mixer)
+MixerStrip::MixerStrip (Mixer_UI& mx, Session* sess, boost::shared_ptr<Route> rt, bool in_mixer)
 	: AxisView(sess)
 	, RouteUI (sess)
 	,_mixer(mx)
@@ -257,8 +257,8 @@ MixerStrip::init ()
 	_packed = false;
 	_embedded = false;
 
-	_session.engine().Stopped.connect (sigc::mem_fun(*this, &MixerStrip::engine_stopped));
-	_session.engine().Running.connect (sigc::mem_fun(*this, &MixerStrip::engine_running));
+	_session->engine().Stopped.connect (sigc::mem_fun(*this, &MixerStrip::engine_stopped));
+	_session->engine().Running.connect (sigc::mem_fun(*this, &MixerStrip::engine_running));
 
 	input_button.signal_button_press_event().connect (sigc::mem_fun(*this, &MixerStrip::input_press), false);
 	output_button.signal_button_press_event().connect (sigc::mem_fun(*this, &MixerStrip::output_press), false);
@@ -312,7 +312,7 @@ MixerStrip::init ()
 
 MixerStrip::~MixerStrip ()
 {
-	GoingAway(); /* EMIT_SIGNAL */
+	drop_references ();
 
 	delete input_selector;
 	delete output_selector;
@@ -363,10 +363,10 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 
 		boost::shared_ptr<AudioTrack> at = audio_track();
 
-		connections.push_back (at->FreezeChange.connect (sigc::mem_fun(*this, &MixerStrip::map_frozen)));
+		connections.add_connection (at->FreezeChange.connect (sigc::mem_fun(*this, &MixerStrip::map_frozen)));
 
 		button_table.attach (*rec_enable_button, 0, 2, 2, 3);
-		rec_enable_button->set_sensitive (_session.writable());
+		rec_enable_button->set_sensitive (_session->writable());
 		rec_enable_button->show();
 
 	} else if (!is_track()) {
@@ -412,31 +412,22 @@ MixerStrip::set_route (boost::shared_ptr<Route> rt)
 						   _("Click to Add/Edit Comments"):
 						   _route->comment());
 
-	connections.push_back (_route->meter_change.connect (
-			sigc::mem_fun(*this, &MixerStrip::meter_changed)));
-	connections.push_back (_route->input()->changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::input_changed)));
-	connections.push_back (_route->output()->changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::output_changed)));
-	connections.push_back (_route->route_group_changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::route_group_changed)));
+	connections.add_connection (_route->meter_change.connect (sigc::mem_fun(*this, &MixerStrip::meter_changed)));
+	connections.add_connection (_route->input()->changed.connect (sigc::mem_fun(*this, &MixerStrip::input_changed)));
+	connections.add_connection (_route->output()->changed.connect (sigc::mem_fun(*this, &MixerStrip::output_changed)));
+	connections.add_connection (_route->route_group_changed.connect (sigc::mem_fun(*this, &MixerStrip::route_group_changed)));
 
 	if (_route->panner()) {
-		connections.push_back (_route->panner()->Changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::connect_to_pan)));
+		connections.add_connection (_route->panner()->Changed.connect (sigc::mem_fun(*this, &MixerStrip::connect_to_pan)));
 	}
 
 	if (is_audio_track()) {
-		connections.push_back (audio_track()->DiskstreamChanged.connect (
-			sigc::mem_fun(*this, &MixerStrip::diskstream_changed)));
+		connections.add_connection (audio_track()->DiskstreamChanged.connect (sigc::mem_fun(*this, &MixerStrip::diskstream_changed)));
 	}
 
-	connections.push_back (_route->NameChanged.connect (
-			sigc::mem_fun(*this, &RouteUI::name_changed)));
-	connections.push_back (_route->comment_changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::comment_changed)));
-	connections.push_back (_route->gui_changed.connect (
-			sigc::mem_fun(*this, &MixerStrip::route_gui_changed)));
+	connections.add_connection (_route->NameChanged.connect (sigc::mem_fun(*this, &RouteUI::name_changed)));
+	connections.add_connection (_route->comment_changed.connect (sigc::mem_fun(*this, &MixerStrip::comment_changed)));
+	connections.add_connection (_route->gui_changed.connect (sigc::mem_fun(*this, &MixerStrip::route_gui_changed)));
 
 	set_stuff_from_route ();
 
@@ -631,7 +622,7 @@ gint
 MixerStrip::output_press (GdkEventButton *ev)
 {
         using namespace Menu_Helpers;
-	if (!_session.engine().connected()) {
+	if (!_session->engine().connected()) {
 	        MessageDialog msg (_("Not connected to JACK - no I/O changes are possible"));
 		msg.run ();
 		return true;
@@ -655,7 +646,7 @@ MixerStrip::output_press (GdkEventButton *ev)
 
 		ARDOUR::BundleList current = _route->output()->bundles_connected ();
 
-		boost::shared_ptr<ARDOUR::BundleList> b = _session.bundles ();
+		boost::shared_ptr<ARDOUR::BundleList> b = _session->bundles ();
 
 		/* give user bundles first chance at being in the menu */
 		
@@ -671,7 +662,7 @@ MixerStrip::output_press (GdkEventButton *ev)
 			}
 		}
 		
-		boost::shared_ptr<ARDOUR::RouteList> routes = _session.get_routes ();
+		boost::shared_ptr<ARDOUR::RouteList> routes = _session->get_routes ();
 		for (ARDOUR::RouteList::const_iterator i = routes->begin(); i != routes->end(); ++i) {
 			maybe_add_bundle_to_output_menu ((*i)->input()->bundle(), current);
 		}
@@ -709,7 +700,7 @@ MixerStrip::edit_output_configuration ()
 			output = _route->output ();
 		}
 		
-		output_selector = new IOSelectorWindow (&_session, output);
+		output_selector = new IOSelectorWindow (_session, output);
 	}
 
 	if (output_selector->is_visible()) {
@@ -723,7 +714,7 @@ void
 MixerStrip::edit_input_configuration ()
 {
 	if (input_selector == 0) {
-		input_selector = new IOSelectorWindow (&_session, _route->input());
+		input_selector = new IOSelectorWindow (_session, _route->input());
 	}
 
 	if (input_selector->is_visible()) {
@@ -742,7 +733,7 @@ MixerStrip::input_press (GdkEventButton *ev)
 	input_menu.set_name ("ArdourContextMenu");
 	citems.clear();
 
-	if (!_session.engine().connected()) {
+	if (!_session->engine().connected()) {
 	        MessageDialog msg (_("Not connected to JACK - no I/O changes are possible"));
 		msg.run ();
 		return true;
@@ -762,7 +753,7 @@ MixerStrip::input_press (GdkEventButton *ev)
 
 		ARDOUR::BundleList current = _route->input()->bundles_connected ();
 
-		boost::shared_ptr<ARDOUR::BundleList> b = _session.bundles ();
+		boost::shared_ptr<ARDOUR::BundleList> b = _session->bundles ();
 
 		/* give user bundles first chance at being in the menu */
 		
@@ -778,7 +769,7 @@ MixerStrip::input_press (GdkEventButton *ev)
 			}
 		}
 		
-		boost::shared_ptr<ARDOUR::RouteList> routes = _session.get_routes ();
+		boost::shared_ptr<ARDOUR::RouteList> routes = _session->get_routes ();
 		for (ARDOUR::RouteList::const_iterator i = routes->begin(); i != routes->end(); ++i) {
 			maybe_add_bundle_to_input_menu ((*i)->output()->bundle(), current);
 		}
@@ -990,7 +981,7 @@ MixerStrip::update_io_button (boost::shared_ptr<ARDOUR::Route> route, Width widt
 	uint32_t io_count;
 	uint32_t io_index;
 	Port *port;
-	vector<string> connections;
+	vector<string> port_connections;
 
 	uint32_t total_connection_count = 0;
 	uint32_t io_connection_count = 0;
@@ -1028,13 +1019,13 @@ MixerStrip::update_io_button (boost::shared_ptr<ARDOUR::Route> route, Width widt
 		} else {
 			port = route->output()->nth (io_index);
 		}
-
-		connections.clear ();
-		port->get_connections(connections);
+		
+		port_connections.clear ();
+		port->get_connections(port_connections);
 		io_connection_count = 0;
 
-		if (!connections.empty()) {
-			for (vector<string>::iterator i = connections.begin(); i != connections.end(); ++i) {
+		if (!port_connections.empty()) {
+			for (vector<string>::iterator i = port_connections.begin(); i != port_connections.end(); ++i) {
 				string& connection_name (*i);
 
 				if (io_connection_count == 0) {
diff --git a/gtk2_ardour/mixer_strip.h b/gtk2_ardour/mixer_strip.h
index d5b247019b..64579e0c33 100644
--- a/gtk2_ardour/mixer_strip.h
+++ b/gtk2_ardour/mixer_strip.h
@@ -79,8 +79,8 @@ class RouteGroupMenu;
 class MixerStrip : public RouteUI, public Gtk::EventBox
 {
   public:
-	MixerStrip (Mixer_UI&, ARDOUR::Session&, boost::shared_ptr<ARDOUR::Route>, bool in_mixer = true);
-	MixerStrip (Mixer_UI&, ARDOUR::Session&, bool in_mixer = true);
+	MixerStrip (Mixer_UI&, ARDOUR::Session*, boost::shared_ptr<ARDOUR::Route>, bool in_mixer = true);
+	MixerStrip (Mixer_UI&, ARDOUR::Session*, bool in_mixer = true);
 	~MixerStrip ();
 
 	void set_width_enum (Width, void* owner);
@@ -167,8 +167,6 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 
 	std::string longest_label;
 
-	sigc::connection newplug_connection;
-
 	gint    mark_update_safe ();
 	guint32 mode_switch_in_progress;
 
@@ -216,8 +214,8 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 	void input_changed (ARDOUR::IOChange, void *);
 	void output_changed (ARDOUR::IOChange, void *);
 
-	sigc::connection panstate_connection;
-	sigc::connection panstyle_connection;
+	boost::signals2::scoped_connection panstate_connection;
+	boost::signals2::scoped_connection panstyle_connection;
 	void connect_to_pan ();
 
 	void update_diskstream_display ();
@@ -267,7 +265,7 @@ class MixerStrip : public RouteUI, public Gtk::EventBox
 	void revert_to_default_display ();
 
 	void drop_send ();
-	sigc::connection send_gone_connection;
+	boost::signals2::scoped_connection send_gone_connection;
 
 	void reset_strip_style ();
 
diff --git a/gtk2_ardour/mixer_ui.cc b/gtk2_ardour/mixer_ui.cc
index 12dde081af..9ec05c020c 100644
--- a/gtk2_ardour/mixer_ui.cc
+++ b/gtk2_ardour/mixer_ui.cc
@@ -64,7 +64,6 @@ using PBD::atoi;
 Mixer_UI::Mixer_UI ()
 	: Window (Gtk::WINDOW_TOPLEVEL)
 {
-	session = 0;
 	_strip_width = Config->get_default_narrow_ms() ? Narrow : Wide;
 	track_menu = 0;
 	route_group_context_menu = 0;
@@ -313,7 +312,7 @@ Mixer_UI::add_strip (RouteList& routes)
 			return;
 		}
 
-		strip = new MixerStrip (*this, *session, route);
+		strip = new MixerStrip (*this, _session, route);
 		strips.push_back (strip);
 
 		Config->get_default_narrow_ms() ? _strip_width = Narrow : _strip_width = Wide;
@@ -336,7 +335,7 @@ Mixer_UI::add_strip (RouteList& routes)
 
 		route->NameChanged.connect (sigc::bind (sigc::mem_fun(*this, &Mixer_UI::strip_name_changed), strip));
 
-		strip->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &Mixer_UI::remove_strip), strip));
+		scoped_connect (strip->GoingAway, boost::bind (&Mixer_UI::remove_strip, this, strip));
 		strip->WidthChanged.connect (sigc::mem_fun(*this, &Mixer_UI::strip_width_changed));
 		strip->signal_button_release_event().connect (sigc::bind (sigc::mem_fun(*this, &Mixer_UI::strip_button_release_event), strip));
 	}
@@ -379,7 +378,7 @@ Mixer_UI::sync_order_keys (string const & src)
 	TreeModel::Children rows = track_model->children();
 	TreeModel::Children::iterator ri;
 
-	if (src == N_("signal") || !session || (session->state_of_the_state() & (Session::Loading|Session::Deletion)) || rows.empty()) {
+	if (src == N_("signal") || !_session || (_session->state_of_the_state() & (Session::Loading|Session::Deletion)) || rows.empty()) {
 		return;
 	}
 
@@ -452,14 +451,24 @@ Mixer_UI::strip_button_release_event (GdkEventButton *ev, MixerStrip *strip)
 }
 
 void
-Mixer_UI::connect_to_session (Session* sess)
+Mixer_UI::set_session (Session* sess)
 {
-	session = sess;
+	SessionHandlePtr::set_session (sess);
+
+	if (_plugin_selector) {
+		_plugin_selector->set_session (_session);
+	}
+
+	_group_tabs->set_session (sess);
+
+	if (!_session) {
+		return;
+	}
 
 	XMLNode* node = ARDOUR_UI::instance()->mixer_settings();
 	set_state (*node);
 
-	WindowTitle title(session->name());
+	WindowTitle title(_session->name());
 	title += _("Mixer");
 	title += Glib::get_application_name();
 
@@ -467,30 +476,24 @@ Mixer_UI::connect_to_session (Session* sess)
 
 	initial_track_display ();
 
-	session->GoingAway.connect (sigc::mem_fun(*this, &Mixer_UI::disconnect_from_session));
-	session->RouteAdded.connect (sigc::mem_fun(*this, &Mixer_UI::add_strip));
-	session->route_group_added.connect (sigc::mem_fun(*this, &Mixer_UI::add_route_group));
-	session->route_group_removed.connect (sigc::mem_fun(*this, &Mixer_UI::route_groups_changed));
-	session->config.ParameterChanged.connect (sigc::mem_fun (*this, &Mixer_UI::parameter_changed));
+	_session_connections.add_connection (_session->RouteAdded.connect (boost::bind (&Mixer_UI::add_strip, this, _1)));
+	_session_connections.add_connection (_session->route_group_added.connect (boost::bind (&Mixer_UI::add_route_group, this, _1)));
+	_session_connections.add_connection (_session->route_group_removed.connect (boost::bind (&Mixer_UI::route_groups_changed, this)));
+	_session_connections.add_connection (_session->config.ParameterChanged.connect (boost::bind (&Mixer_UI::parameter_changed, this, _1)));
 
 	route_groups_changed ();
 
-	if (_plugin_selector)
-		_plugin_selector->set_session (session);
-
 	if (_visible) {
 	       show_window();
 	}
 
-	_group_tabs->connect_to_session (sess);
-
 	start_updating ();
 }
 
 void
-Mixer_UI::disconnect_from_session ()
+Mixer_UI::session_going_away ()
 {
-	ENSURE_GUI_THREAD (*this, &Mixer_UI::disconnect_from_session)
+	ENSURE_GUI_THREAD (*this, &Mixer_UI::session_going_away)
 
 	group_model->clear ();
 	_selection.clear ();
@@ -500,6 +503,8 @@ Mixer_UI::disconnect_from_session ()
 	set_title (title.get_string());
 
 	stop_updating ();
+
+	SessionHandlePtr::session_going_away ();
 }
 
 void
@@ -551,7 +556,7 @@ Mixer_UI::stop_updating ()
 void
 Mixer_UI::fast_update_strips ()
 {
-	if (is_mapped () && session) {
+	if (is_mapped () && _session) {
 		for (list<MixerStrip *>::iterator i = strips.begin(); i != strips.end(); ++i) {
 			(*i)->fast_update ();
 		}
@@ -670,7 +675,7 @@ void
 Mixer_UI::track_list_reorder (const TreeModel::Path&, const TreeModel::iterator&, int* /*new_order*/)
 {
 	strip_redisplay_does_not_sync_order_keys = true;
-	session->set_remote_control_ids();
+	_session->set_remote_control_ids();
 	redisplay_track_list ();
 	strip_redisplay_does_not_sync_order_keys = false;
 }
@@ -680,7 +685,7 @@ Mixer_UI::track_list_change (const Gtk::TreeModel::Path&, const Gtk::TreeModel::
 {
 	// never reset order keys because of a property change
 	strip_redisplay_does_not_reset_order_keys = true;
-	session->set_remote_control_ids();
+	_session->set_remote_control_ids();
 	redisplay_track_list ();
 	strip_redisplay_does_not_reset_order_keys = false;
 }
@@ -689,8 +694,10 @@ void
 Mixer_UI::track_list_delete (const Gtk::TreeModel::Path&)
 {
 	/* this could require an order sync */
-	session->set_remote_control_ids();
-	redisplay_track_list ();
+	if (_session && !_session->deletion_in_progress()) {
+		_session->set_remote_control_ids();
+		redisplay_track_list ();
+	}
 }
 
 void
@@ -757,7 +764,7 @@ Mixer_UI::redisplay_track_list ()
 	}
 
 	if (!strip_redisplay_does_not_reset_order_keys && !strip_redisplay_does_not_sync_order_keys) {
-		session->sync_order_keys (N_("signal"));
+		_session->sync_order_keys (N_("signal"));
 	}
 
 	// Resigc::bind all of the midi controls automatically
@@ -887,7 +894,7 @@ struct SignalOrderRouteSorter {
 void
 Mixer_UI::initial_track_display ()
 {
-	boost::shared_ptr<RouteList> routes = session->get_routes();
+	boost::shared_ptr<RouteList> routes = _session->get_routes();
 	RouteList copy (*routes);
 	SignalOrderRouteSorter sorter;
 
@@ -1076,13 +1083,13 @@ Mixer_UI::group_display_button_press (GdkEventButton* ev)
 void
 Mixer_UI::activate_all_route_groups ()
 {
-	session->foreach_route_group (sigc::bind (sigc::mem_fun (*this, &Mixer_UI::set_route_group_activation), true));
+	_session->foreach_route_group (sigc::bind (sigc::mem_fun (*this, &Mixer_UI::set_route_group_activation), true));
 }
 
 void
 Mixer_UI::disable_all_route_groups ()
 {
-	session->foreach_route_group (sigc::bind (sigc::mem_fun (*this, &Mixer_UI::set_route_group_activation), false));
+	_session->foreach_route_group (sigc::bind (sigc::mem_fun (*this, &Mixer_UI::set_route_group_activation), false));
 }
 
 void
@@ -1102,13 +1109,13 @@ Mixer_UI::route_groups_changed ()
 		row[group_columns.group] = 0;
 	}
 
-	session->foreach_route_group (sigc::mem_fun (*this, &Mixer_UI::add_route_group));
+	_session->foreach_route_group (sigc::mem_fun (*this, &Mixer_UI::add_route_group));
 }
 
 void
 Mixer_UI::new_route_group ()
 {
-	session->add_route_group (new RouteGroup (*session, "", RouteGroup::Active, (RouteGroup::Property) (RouteGroup::Gain |RouteGroup::Mute | RouteGroup::Solo)));
+	_session->add_route_group (new RouteGroup (*_session, "", RouteGroup::Active, (RouteGroup::Property) (RouteGroup::Gain |RouteGroup::Mute | RouteGroup::Solo)));
 }
 
 void
@@ -1131,7 +1138,7 @@ Mixer_UI::remove_selected_route_group ()
 		RouteGroup* rg = (*iter)[group_columns.group];
 
 		if (rg) {
-			session->remove_route_group (*rg);
+			_session->remove_route_group (*rg);
 		}
 	}
 }
@@ -1541,7 +1548,7 @@ void
 Mixer_UI::parameter_changed (string const & p)
 {
 	if (p == "show-group-tabs") {
-		bool const s = session->config.get_show_group_tabs ();
+		bool const s = _session->config.get_show_group_tabs ();
 		if (s) {
 			_group_tabs->show ();
 		} else {
diff --git a/gtk2_ardour/mixer_ui.h b/gtk2_ardour/mixer_ui.h
index 2945e00858..275c0151cd 100644
--- a/gtk2_ardour/mixer_ui.h
+++ b/gtk2_ardour/mixer_ui.h
@@ -33,8 +33,10 @@
 #include <gtkmm/treeview.h>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/ardour.h"
+#include "ardour/session_handle.h"
 
 #include "route_processor_selection.h"
 #include "enums.h"
@@ -42,7 +44,6 @@
 namespace ARDOUR {
 	class Route;
 	class RouteGroup;
-	class Session;
 	class AudioDiskstream;
 };
 
@@ -50,13 +51,13 @@ class MixerStrip;
 class PluginSelector;
 class MixerGroupTabs;
 
-class Mixer_UI : public Gtk::Window
+class Mixer_UI : public Gtk::Window, public PBD::ScopedConnectionList, public ARDOUR::SessionHandlePtr
 {
   public:
 	Mixer_UI ();
 	~Mixer_UI();
 
-	void connect_to_session (ARDOUR::Session *);
+	void set_session (ARDOUR::Session *);
 
 	PluginSelector* plugin_selector();
 
@@ -81,8 +82,6 @@ class Mixer_UI : public Gtk::Window
 	RouteRedirectSelection& selection() { return _selection; }
 
   private:
-	ARDOUR::Session         *session;
-
 	bool					_visible;
 
 	Gtk::HBox				global_hpacker;
@@ -146,7 +145,7 @@ class Mixer_UI : public Gtk::Window
 	gint start_updating ();
 	gint stop_updating ();
 
-	void disconnect_from_session ();
+	void session_going_away ();
 
 	sigc::connection fast_screen_update_connection;
 	void fast_update_strips ();
diff --git a/gtk2_ardour/panner_ui.cc b/gtk2_ardour/panner_ui.cc
index 3c2cfafdfe..7e80c9e641 100644
--- a/gtk2_ardour/panner_ui.cc
+++ b/gtk2_ardour/panner_ui.cc
@@ -48,19 +48,20 @@ using namespace Gtk;
 
 const int PannerUI::pan_bar_height = 30;
 
-PannerUI::PannerUI (Session& s)
-	: _session (s),
-	  _current_nouts (-1),
-	  _current_npans (-1),
-	  hAdjustment(0.0, 0.0, 0.0),
-	  vAdjustment(0.0, 0.0, 0.0),
-	  panning_viewport(hAdjustment, vAdjustment),
-	  panning_up_arrow (Gtk::ARROW_UP, Gtk::SHADOW_OUT),
-	  panning_down_arrow (Gtk::ARROW_DOWN, Gtk::SHADOW_OUT),
-	  panning_link_button (_("link")),
-	  pan_automation_style_button (""),
-	  pan_automation_state_button ("")
-{
+PannerUI::PannerUI (Session* s)
+	: _current_nouts (-1)
+	, _current_npans (-1)
+	, hAdjustment(0.0, 0.0, 0.0)
+	, vAdjustment(0.0, 0.0, 0.0)
+	, panning_viewport(hAdjustment, vAdjustment)
+	, panning_up_arrow (Gtk::ARROW_UP, Gtk::SHADOW_OUT)
+	, panning_down_arrow (Gtk::ARROW_DOWN, Gtk::SHADOW_OUT)
+	, panning_link_button (_("link"))
+	, pan_automation_style_button ("")
+	, pan_automation_state_button ("")
+{
+	set_session (s);
+
 	ignore_toggle = false;
 	pan_menu = 0;
 	pan_astate_menu = 0;
@@ -133,7 +134,7 @@ PannerUI::PannerUI (Session& s)
 void
 PannerUI::set_panner (boost::shared_ptr<Panner> p)
 {
- 	connections.clear ();
+ 	connections.drop_connections ();
 
 	delete pan_astyle_menu;
 	pan_astyle_menu = 0;
@@ -150,9 +151,9 @@ PannerUI::set_panner (boost::shared_ptr<Panner> p)
 		return;
 	}
 
- 	connections.push_back (_panner->Changed.connect (sigc::mem_fun(*this, &PannerUI::panner_changed)));
- 	connections.push_back (_panner->LinkStateChanged.connect (sigc::mem_fun(*this, &PannerUI::update_pan_linkage)));
- 	connections.push_back (_panner->StateChanged.connect (sigc::mem_fun(*this, &PannerUI::update_pan_state)));
+ 	connections.add_connection (_panner->Changed.connect (sigc::mem_fun(*this, &PannerUI::panner_changed)));
+ 	connections.add_connection (_panner->LinkStateChanged.connect (sigc::mem_fun(*this, &PannerUI::update_pan_linkage)));
+ 	connections.add_connection (_panner->StateChanged.connect (sigc::mem_fun(*this, &PannerUI::update_pan_state)));
 
 	setup_pan ();
 
@@ -644,7 +645,7 @@ PannerUI::pan_adjustment_changed (uint32_t which)
 			   the panner objects have no access to the session,
 			   so do this here. ick.
 			*/
-			_session.set_dirty();
+			_session->set_dirty();
 		}
 	}
 }
diff --git a/gtk2_ardour/panner_ui.h b/gtk2_ardour/panner_ui.h
index bebffec6c0..de889471aa 100644
--- a/gtk2_ardour/panner_ui.h
+++ b/gtk2_ardour/panner_ui.h
@@ -33,6 +33,8 @@
 #include <gtkmm2ext/click_box.h>
 #include <gtkmm2ext/slider_controller.h>
 
+#include "ardour/session_handle.h"
+
 #include "enums.h"
 
 class Panner2d;
@@ -53,10 +55,10 @@ namespace Gtk {
 	class Menuitem;
 }
 
-class PannerUI : public Gtk::HBox
+class PannerUI : public Gtk::HBox, public ARDOUR::SessionHandlePtr
 {
   public:
-	PannerUI (ARDOUR::Session&);
+	PannerUI (ARDOUR::Session*);
 	~PannerUI ();
 
 	virtual void set_panner (boost::shared_ptr<ARDOUR::Panner>);
@@ -80,8 +82,7 @@ class PannerUI : public Gtk::HBox
 	friend class MixerStrip;
 
 	boost::shared_ptr<ARDOUR::Panner> _panner;
-	ARDOUR::Session& _session;
-	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList connections;
 
 	bool ignore_toggle;
 	bool in_pan_update;
diff --git a/gtk2_ardour/playlist_selector.cc b/gtk2_ardour/playlist_selector.cc
index abf249fb3d..aa678e80a3 100644
--- a/gtk2_ardour/playlist_selector.cc
+++ b/gtk2_ardour/playlist_selector.cc
@@ -111,7 +111,7 @@ PlaylistSelector::show_for (RouteUI* ruix)
 
 	model->clear ();
 
-	session->playlists->foreach (this, &PlaylistSelector::add_playlist_to_map);
+	_session->playlists->foreach (this, &PlaylistSelector::add_playlist_to_map);
 
 	this_ds = rui->get_diskstream();
 
@@ -123,7 +123,7 @@ PlaylistSelector::show_for (RouteUI* ruix)
 
 	for (DSPL_Map::iterator x = dspl_map.begin(); x != dspl_map.end(); ++x) {
 
-		boost::shared_ptr<Diskstream> ds = session->diskstream_by_id (x->first);
+		boost::shared_ptr<Diskstream> ds = _session->diskstream_by_id (x->first);
 
 		if (ds == 0) {
 			continue;
@@ -179,7 +179,7 @@ PlaylistSelector::show_for (RouteUI* ruix)
 
 	// Add unassigned (imported) playlists to the list
 	list<boost::shared_ptr<Playlist> > unassigned;
-	session->playlists->unassigned (unassigned);
+	_session->playlists->unassigned (unassigned);
 
 	TreeModel::Row row;
 	TreeModel::Row* selected_row = 0;
@@ -236,18 +236,6 @@ PlaylistSelector::add_playlist_to_map (boost::shared_ptr<Playlist> pl)
 }
 
 void
-PlaylistSelector::set_session (Session* s)
-{
-	ENSURE_GUI_THREAD (*this, &PlaylistSelector::set_session, s)
-
-	session = s;
-
-	if (session) {
-		session->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &PlaylistSelector::set_session), static_cast<Session*> (0)));
-	}
-}
-
-void
 PlaylistSelector::close_button_click ()
 {
 	rui = 0;
diff --git a/gtk2_ardour/playlist_selector.h b/gtk2_ardour/playlist_selector.h
index 828607284f..d0b36fae48 100644
--- a/gtk2_ardour/playlist_selector.h
+++ b/gtk2_ardour/playlist_selector.h
@@ -29,6 +29,7 @@
 #include <gtkmm2ext/selector.h>
 
 #include "ardour_dialog.h"
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 	class Session;
@@ -44,7 +45,6 @@ class PlaylistSelector : public ArdourDialog
 	PlaylistSelector ();
 	~PlaylistSelector ();
 
-	void set_session (ARDOUR::Session*);
 	void show_for (RouteUI*);
 
   protected:
@@ -53,7 +53,6 @@ class PlaylistSelector : public ArdourDialog
   private:
 	typedef std::map<PBD::ID,std::list<boost::shared_ptr<ARDOUR::Playlist> >*> DSPL_Map;
 
-	ARDOUR::Session* session;
 	Gtk::ScrolledWindow scroller;
 	DSPL_Map dspl_map;
 	RouteUI* rui;
diff --git a/gtk2_ardour/plugin_selector.cc b/gtk2_ardour/plugin_selector.cc
index 32e43b20da..35befc0d69 100644
--- a/gtk2_ardour/plugin_selector.cc
+++ b/gtk2_ardour/plugin_selector.cc
@@ -72,7 +72,6 @@ PluginSelector::PluginSelector (PluginManager *mgr)
 
 	_plugin_menu = 0;
 	manager = mgr;
-	session = 0;
 	in_row_change = false;
 
 	manager->PluginListChanged.connect (sigc::mem_fun (*this, &PluginSelector::build_plugin_menu));
@@ -205,18 +204,6 @@ PluginSelector::row_clicked(GdkEventButton* event)
 		btn_add_clicked();
 }
 
-void
-PluginSelector::set_session (Session* s)
-{
-	ENSURE_GUI_THREAD (*this, &PluginSelector::set_session, s)
-
-	session = s;
-
-	if (session) {
-		session->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &PluginSelector::set_session), static_cast<Session*> (0)));
-	}
-}
-
 bool
 PluginSelector::show_this_plugin (const PluginInfoPtr& info, const std::string& filterstr)
 {
@@ -384,11 +371,11 @@ PluginSelector::au_refiller (const std::string&)
 PluginPtr
 PluginSelector::load_plugin (PluginInfoPtr pi)
 {
-	if (session == 0) {
+	if (_session == 0) {
 		return PluginPtr();
 	}
 
-	return pi->load (*session);
+	return pi->load (*_session);
 }
 
 void
diff --git a/gtk2_ardour/plugin_selector.h b/gtk2_ardour/plugin_selector.h
index 06e746853f..7e0c66b60f 100644
--- a/gtk2_ardour/plugin_selector.h
+++ b/gtk2_ardour/plugin_selector.h
@@ -26,6 +26,7 @@
 #include <gtkmm2ext/selector.h>
 
 #include "ardour/plugin.h"
+#include "ardour/session_handle.h"
 #include "plugin_interest.h"
 
 namespace ARDOUR {
@@ -43,7 +44,6 @@ class PluginSelector : public ArdourDialog
 
 	int run (); // XXX should we try not to overload the non-virtual Gtk::Dialog::run() ?
 
-	void set_session (ARDOUR::Session*);
 	void on_show ();
 
 	Gtk::Menu* plugin_menu ();
@@ -52,7 +52,6 @@ class PluginSelector : public ArdourDialog
   private:
 	PluginInterestedObject* interested_object;
 
-	ARDOUR::Session* session;
 	Gtk::ScrolledWindow scroller;   // Available plugins
 	Gtk::ScrolledWindow ascroller;  // Added plugins
 
diff --git a/gtk2_ardour/plugin_ui.cc b/gtk2_ardour/plugin_ui.cc
index cb7491917c..dd2b0b204d 100644
--- a/gtk2_ardour/plugin_ui.cc
+++ b/gtk2_ardour/plugin_ui.cc
@@ -415,8 +415,8 @@ PlugUIBase::PlugUIBase (boost::shared_ptr<PluginInsert> pi)
 
 	plugin_analysis_expander.property_expanded().signal_changed().connect( sigc::mem_fun(*this, &PlugUIBase::toggle_plugin_analysis));
 	plugin_analysis_expander.set_expanded(false);
-
-	insert->GoingAway.connect (sigc::mem_fun (*this, &PlugUIBase::plugin_going_away));
+	
+	death_connection = insert->GoingAway.connect (sigc::mem_fun (*this, &PlugUIBase::plugin_going_away));
 }
 
 PlugUIBase::~PlugUIBase()
@@ -430,6 +430,7 @@ PlugUIBase::plugin_going_away ()
 	/* drop references to the plugin/insert */
 	insert.reset ();
 	plugin.reset ();
+	death_connection.disconnect ();
 }
 
 void
diff --git a/gtk2_ardour/plugin_ui.h b/gtk2_ardour/plugin_ui.h
index 221c1d71f1..cf1bcd0ed8 100644
--- a/gtk2_ardour/plugin_ui.h
+++ b/gtk2_ardour/plugin_ui.h
@@ -121,6 +121,7 @@ class PlugUIBase : public virtual sigc::trackable
 	void toggle_plugin_analysis ();
 	void processor_active_changed (boost::weak_ptr<ARDOUR::Processor> p);
 	void plugin_going_away ();
+	boost::signals2::scoped_connection death_connection;
 };
 
 class GenericPluginUI : public PlugUIBase, public Gtk::VBox
@@ -260,7 +261,7 @@ class PluginUIWindow : public Gtk::Window
   private:
 	Glib::ustring _title;
 	PlugUIBase* _pluginui;
-	sigc::connection death_connection;
+	boost::signals2::scoped_connection death_connection;
 	Gtk::Window* parent;
 	Gtk::VBox vbox;
 	bool non_gtk_gui;
diff --git a/gtk2_ardour/point_selection.h b/gtk2_ardour/point_selection.h
index 0b89f34454..1b442d279b 100644
--- a/gtk2_ardour/point_selection.h
+++ b/gtk2_ardour/point_selection.h
@@ -21,6 +21,7 @@
 #define __ardour_gtk_point_selection_h__
 
 #include <list>
+#include <boost/noncopyable.hpp>
 
 #include "automation_selectable.h"
 
diff --git a/gtk2_ardour/port_group.cc b/gtk2_ardour/port_group.cc
index 1d36a52364..11e75c1fc3 100644
--- a/gtk2_ardour/port_group.cc
+++ b/gtk2_ardour/port_group.cc
@@ -50,6 +50,14 @@ PortGroup::PortGroup (std::string const & n)
 
 }
 
+PortGroup::~PortGroup()
+{
+	for (BundleList::iterator i = _bundles.begin(); i != _bundles.end(); ++i) {
+		delete *i;
+	}
+	_bundles.clear ();
+}
+
 /** Add a bundle to a group.
  *  @param b Bundle.
  *  @param allow_dups true to allow the group to contain more than one bundle with the same port, otherwise false.
@@ -80,6 +88,14 @@ PortGroup::add_bundle (boost::shared_ptr<Bundle> b, boost::shared_ptr<IO> io, Gd
 	add_bundle_internal (b, io, true, c, false);
 }
 
+PortGroup::BundleRecord::BundleRecord (boost::shared_ptr<ARDOUR::Bundle> b, boost::shared_ptr<ARDOUR::IO> iop, Gdk::Color c, bool has_c)
+	: bundle (b)
+	, io (iop)
+	, colour (c)
+	, has_colour (has_c)
+{
+}
+
 void
 PortGroup::add_bundle_internal (boost::shared_ptr<Bundle> b, boost::shared_ptr<IO> io, bool has_colour, Gdk::Color colour, bool allow_dups)
 {
@@ -90,7 +106,7 @@ PortGroup::add_bundle_internal (boost::shared_ptr<Bundle> b, boost::shared_ptr<I
 		/* don't add this bundle if we already have one with the same ports */
 		
 		BundleList::iterator i = _bundles.begin ();
-		while (i != _bundles.end() && b->has_same_ports (i->bundle) == false) {
+		while (i != _bundles.end() && b->has_same_ports ((*i)->bundle) == false) {
 			++i;
 		}
 		
@@ -99,14 +115,9 @@ PortGroup::add_bundle_internal (boost::shared_ptr<Bundle> b, boost::shared_ptr<I
 		}
 	}
 
-	BundleRecord r;
-	r.bundle = b;
-	r.io = io;
-	r.colour = colour;
-	r.has_colour = has_colour;
-	r.changed_connection = b->Changed.connect (sigc::mem_fun (*this, &PortGroup::bundle_changed));
-
-	_bundles.push_back (r);
+	BundleRecord* br = new BundleRecord (b, io, colour, has_colour);
+	br->changed_connection = b->Changed.connect (boost::bind (&PortGroup::bundle_changed, this, _1));
+	_bundles.push_back (br);
 
 	Changed ();	
 }
@@ -117,7 +128,7 @@ PortGroup::remove_bundle (boost::shared_ptr<Bundle> b)
 	assert (b.get());
 
 	BundleList::iterator i = _bundles.begin ();
-	while (i != _bundles.end() && i->bundle != b) {
+	while (i != _bundles.end() && (*i)->bundle != b) {
 		++i;
 	}
 
@@ -125,7 +136,7 @@ PortGroup::remove_bundle (boost::shared_ptr<Bundle> b)
 		return;
 	}
 
-	i->changed_connection.disconnect ();
+	delete *i;
 	_bundles.erase (i);
 
 	Changed ();
@@ -142,7 +153,7 @@ void
 PortGroup::clear ()
 {
 	for (BundleList::iterator i = _bundles.begin(); i != _bundles.end(); ++i) {
-		i->changed_connection.disconnect ();
+		delete *i;
 	}
 
 	_bundles.clear ();
@@ -153,7 +164,7 @@ bool
 PortGroup::has_port (std::string const& p) const
 {
 	for (BundleList::const_iterator i = _bundles.begin(); i != _bundles.end(); ++i) {
-		if (i->bundle->offers_port_alone (p)) {
+		if ((*i)->bundle->offers_port_alone (p)) {
 			return true;
 		}
 	}
@@ -165,7 +176,7 @@ boost::shared_ptr<Bundle>
 PortGroup::only_bundle ()
 {
 	assert (_bundles.size() == 1);
-	return _bundles.front().bundle;
+	return _bundles.front()->bundle;
 }
 
 
@@ -174,7 +185,7 @@ PortGroup::total_channels () const
 {
 	uint32_t n = 0;
 	for (BundleList::const_iterator i = _bundles.begin(); i != _bundles.end(); ++i) {
-		n += i->bundle->nchannels ();
+		n += (*i)->bundle->nchannels ();
 	}
 
 	return n;
@@ -184,7 +195,7 @@ boost::shared_ptr<IO>
 PortGroup::io_from_bundle (boost::shared_ptr<ARDOUR::Bundle> b) const
 {
 	BundleList::const_iterator i = _bundles.begin ();
-	while (i != _bundles.end() && i->bundle != b) {
+	while (i != _bundles.end() && (*i)->bundle != b) {
 		++i;
 	}
 
@@ -192,7 +203,7 @@ PortGroup::io_from_bundle (boost::shared_ptr<ARDOUR::Bundle> b) const
 		return boost::shared_ptr<IO> ();
 	}
 
-	return i->io;
+	return (*i)->io;
 }
 
 
@@ -204,6 +215,11 @@ PortGroupList::PortGroupList ()
 
 }
 
+PortGroupList::~PortGroupList() 
+{
+	/* XXX need to clean up bundles, but ownership shared with PortGroups */
+}
+
 void
 PortGroupList::set_type (DataType t)
 {
@@ -272,7 +288,7 @@ PortGroupList::gather (ARDOUR::Session* session, bool inputs, bool allow_dups)
 
 		route_bundles.push_back (io->bundle ());
 
-		(*i)->foreach_processor (sigc::bind (sigc::mem_fun (*this, &PortGroupList::maybe_add_processor_to_list), &route_bundles, inputs, used_io));
+		(*i)->foreach_processor (boost::bind (&PortGroupList::maybe_add_processor_to_list, this, _1, &route_bundles, inputs, used_io));
 
 		/* Work out which group to put these bundles in */
 		boost::shared_ptr<PortGroup> g;
@@ -463,13 +479,7 @@ void
 PortGroupList::clear ()
 {
 	_groups.clear ();
-
-	for (std::vector<sigc::connection>::iterator i = _bundle_changed_connections.begin(); i != _bundle_changed_connections.end(); ++i) {
-		i->disconnect ();
-	}
-
-	_bundle_changed_connections.clear ();
-
+	_bundle_changed_connections.drop_connections ();
 	emit_changed ();
 }
 
@@ -513,9 +523,7 @@ PortGroupList::add_group (boost::shared_ptr<PortGroup> g)
 
 	g->Changed.connect (sigc::mem_fun (*this, &PortGroupList::emit_changed));
 
-	_bundle_changed_connections.push_back (
-		g->BundleChanged.connect (sigc::mem_fun (*this, &PortGroupList::emit_bundle_changed))
-		);
+	_bundle_changed_connections.add_connection (g->BundleChanged.connect (sigc::mem_fun (*this, &PortGroupList::emit_bundle_changed)));
 
 	emit_changed ();
 }
diff --git a/gtk2_ardour/port_group.h b/gtk2_ardour/port_group.h
index 1fcceb4c19..ebab997699 100644
--- a/gtk2_ardour/port_group.h
+++ b/gtk2_ardour/port_group.h
@@ -23,9 +23,12 @@
 #include <vector>
 #include <string>
 #include <set>
+#include <boost/shared_ptr.hpp>
+#include <boost/signals2.hpp>
+
 #include <gtkmm/widget.h>
 #include <gtkmm/checkbutton.h>
-#include <boost/shared_ptr.hpp>
+
 #include "ardour/data_type.h"
 #include "ardour/types.h"
 
@@ -47,6 +50,7 @@ class PortGroup : public sigc::trackable
 {
 public:
 	PortGroup (std::string const & n);
+	~PortGroup ();
 
 	void add_bundle (boost::shared_ptr<ARDOUR::Bundle>, bool allow_dups = false);
 	void add_bundle (boost::shared_ptr<ARDOUR::Bundle>, boost::shared_ptr<ARDOUR::IO> io);
@@ -65,19 +69,21 @@ public:
 	sigc::signal<void> Changed;
 
 	/** An individual bundle on our list has changed in some way */
-	sigc::signal<void, ARDOUR::Bundle::Change> BundleChanged;
+	boost::signals2::signal<void(ARDOUR::Bundle::Change)> BundleChanged;
 
 	struct BundleRecord {
-		boost::shared_ptr<ARDOUR::Bundle> bundle;
-		/** IO whose ports are in the bundle, or 0.  This is so that we can do things like adding
-		    ports to the IO from matrix editor menus. */
-		boost::shared_ptr<ARDOUR::IO> io; 
-		Gdk::Color colour;
-		bool has_colour;
-		sigc::connection changed_connection;
+	    boost::shared_ptr<ARDOUR::Bundle> bundle;
+	    /** IO whose ports are in the bundle, or 0.  This is so that we can do things like adding
+		ports to the IO from matrix editor menus. */
+	    boost::shared_ptr<ARDOUR::IO> io; 
+	    Gdk::Color colour;
+	    bool has_colour;
+	    boost::signals2::scoped_connection changed_connection;
+
+	    BundleRecord (boost::shared_ptr<ARDOUR::Bundle>, boost::shared_ptr<ARDOUR::IO>, Gdk::Color, bool has_colour);
 	};
 
-	typedef std::list<BundleRecord> BundleList;
+	typedef std::list<BundleRecord*> BundleList;
 
 	BundleList const & bundles () const {
 		return _bundles;
@@ -95,6 +101,7 @@ class PortGroupList : public sigc::trackable
 {
   public:
 	PortGroupList ();
+	~PortGroupList();
 
 	typedef std::vector<boost::shared_ptr<PortGroup> > List;
 
@@ -125,10 +132,10 @@ class PortGroupList : public sigc::trackable
 	bool empty () const;
 
 	/** The group list has changed in some way; a group has been added or removed, or the list cleared etc. */
-	sigc::signal<void> Changed;
+	boost::signals2::signal<void()> Changed;
 
 	/** A bundle in one of our groups has changed */
-	sigc::signal<void, ARDOUR::Bundle::Change> BundleChanged;
+	boost::signals2::signal<void(ARDOUR::Bundle::Change)> BundleChanged;
 
   private:
 	bool port_has_prefix (std::string const &, std::string const &) const;
@@ -144,7 +151,7 @@ class PortGroupList : public sigc::trackable
 	ARDOUR::DataType _type;
 	mutable PortGroup::BundleList _bundles;
 	List _groups;
-	std::vector<sigc::connection> _bundle_changed_connections;
+	PBD::ScopedConnectionList _bundle_changed_connections;
 	bool _signals_suspended;
 	bool _pending_change;
 	ARDOUR::Bundle::Change _pending_bundle_change;
diff --git a/gtk2_ardour/port_matrix.cc b/gtk2_ardour/port_matrix.cc
index b9285de7c7..9d5187ca2e 100644
--- a/gtk2_ardour/port_matrix.cc
+++ b/gtk2_ardour/port_matrix.cc
@@ -45,19 +45,20 @@ using namespace ARDOUR;
  *  @param type Port type that we are handling.
  */
 PortMatrix::PortMatrix (Window* parent, Session* session, DataType type)
-	: Table (3, 3),
-	  _session (session),
-	  _parent (parent),
-	  _type (type),
-	  _menu (0),
-	  _arrangement (TOP_TO_RIGHT),
-	  _row_index (0),
-	  _column_index (1),
-	  _min_height_divisor (1),
-	  _show_only_bundles (false),
-	  _inhibit_toggle_show_only_bundles (false),
-	  _ignore_notebook_page_selected (false)
-{
+	: Table (3, 3)
+	, _parent (parent)
+	, _type (type)
+	, _menu (0)
+	, _arrangement (TOP_TO_RIGHT)
+	, _row_index (0)
+	, _column_index (1)
+	, _min_height_divisor (1)
+	, _show_only_bundles (false)
+	, _inhibit_toggle_show_only_bundles (false)
+	, _ignore_notebook_page_selected (false)
+{
+	set_session (session);
+
 	_body = new PortMatrixBody (this);
 	_body->DimensionsChanged.connect (sigc::mem_fun (*this, &PortMatrix::body_dimensions_changed));
 
@@ -148,15 +149,13 @@ PortMatrix::init ()
 	/* Part 2: notice when things have changed that require our subclass to clear and refill _ports[] */
 	
 	/* watch for routes being added or removed */
-	_session->RouteAdded.connect (sigc::hide (sigc::mem_fun (*this, &PortMatrix::routes_changed)));
+	_session_connections.add_connection (_session->RouteAdded.connect (boost::bind (&PortMatrix::routes_changed, this)));
 
 	/* and also bundles */
-	_session->BundleAdded.connect (sigc::hide (sigc::mem_fun (*this, &PortMatrix::setup_global_ports)));
+	_session_connections.add_connection (_session->BundleAdded.connect (boost::bind (&PortMatrix::setup_global_ports, this)));
 
 	/* and also ports */
-	_session->engine().PortRegisteredOrUnregistered.connect (sigc::mem_fun (*this, &PortMatrix::setup_global_ports));
-
-	_session->GoingAway.connect (sigc::mem_fun (*this, &PortMatrix::session_going_away));
+	_session_connections.add_connection (_session->engine().PortRegisteredOrUnregistered.connect (boost::bind (&PortMatrix::setup_global_ports, this)));
 
 	reconnect_to_routes ();
 	
@@ -167,16 +166,11 @@ PortMatrix::init ()
 void
 PortMatrix::reconnect_to_routes ()
 {
-	for (vector<sigc::connection>::iterator i = _route_connections.begin(); i != _route_connections.end(); ++i) {
-		i->disconnect ();
-	}
-	_route_connections.clear ();
+	_route_connections.drop_connections ();
 
 	boost::shared_ptr<RouteList> routes = _session->get_routes ();
 	for (RouteList::iterator i = routes->begin(); i != routes->end(); ++i) {
-		_route_connections.push_back (
-			(*i)->processors_changed.connect (sigc::mem_fun (*this, &PortMatrix::route_processors_changed))
-			);
+		_route_connections.add_connection ((*i)->processors_changed.connect (sigc::mem_fun (*this, &PortMatrix::route_processors_changed)));
 	}
 }
 
@@ -261,13 +255,13 @@ PortMatrix::disassociate_all ()
 	PortGroup::BundleList b = _ports[1].bundles ();
 
 	for (PortGroup::BundleList::iterator i = a.begin(); i != a.end(); ++i) {
-		for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
+		for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
 			for (PortGroup::BundleList::iterator k = b.begin(); k != b.end(); ++k) {
-				for (uint32_t l = 0; l < k->bundle->nchannels(); ++l) {
+				for (uint32_t l = 0; l < (*k)->bundle->nchannels(); ++l) {
 
 					BundleChannel c[2] = {
-						BundleChannel (i->bundle, j),
-						BundleChannel (k->bundle, l)
+						BundleChannel ((*i)->bundle, j),
+						BundleChannel ((*k)->bundle, l)
 							};
 
 					if (get_state (c) == PortMatrixNode::ASSOCIATED) {
@@ -493,11 +487,11 @@ PortMatrix::disassociate_all_on_channel (boost::weak_ptr<Bundle> bundle, uint32_
 	PortGroup::BundleList a = _ports[1-dim].bundles ();
 
 	for (PortGroup::BundleList::iterator i = a.begin(); i != a.end(); ++i) {
-		for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
+		for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
 
 			BundleChannel c[2];
 			c[dim] = BundleChannel (sb, channel);
-			c[1-dim] = BundleChannel (i->bundle, j);
+			c[1-dim] = BundleChannel ((*i)->bundle, j);
 
 			if (get_state (c) == PortMatrixNode::ASSOCIATED) {
 				set_state (c, false);
diff --git a/gtk2_ardour/port_matrix.h b/gtk2_ardour/port_matrix.h
index cfa4cdbadc..950d5bfd32 100644
--- a/gtk2_ardour/port_matrix.h
+++ b/gtk2_ardour/port_matrix.h
@@ -28,8 +28,11 @@
 #include <gtkmm/checkbutton.h>
 #include <gtkmm/notebook.h>
 #include <boost/shared_ptr.hpp>
+
 #include "ardour/bundle.h"
 #include "ardour/types.h"
+#include "ardour/session_handle.h"
+
 #include "port_group.h"
 #include "port_matrix_types.h"
 #include "i18n.h"
@@ -55,7 +58,7 @@ namespace Gtk {
 
 class PortMatrixBody;
 
-class PortMatrix : public Gtk::Table
+class PortMatrix : public Gtk::Table, public ARDOUR::SessionHandlePtr
 {
 public:
 	PortMatrix (Gtk::Window*, ARDOUR::Session *, ARDOUR::DataType);
@@ -160,7 +163,6 @@ protected:
 	    from left to right as you go from list 0 to list 1.  Hence subclasses which deal with
 	    inputs and outputs should put outputs in list 0 and inputs in list 1. */
 	PortGroupList _ports[2];
-	ARDOUR::Session* _session;
 
 private:
 
@@ -190,7 +192,7 @@ private:
 
 	/// port type that we are working with
 	ARDOUR::DataType _type;
-	std::vector<sigc::connection> _route_connections;
+	PBD::ScopedConnectionList _route_connections;
 
 	PortMatrixBody* _body;
 	Gtk::HScrollbar _hscroll;
diff --git a/gtk2_ardour/port_matrix_body.cc b/gtk2_ardour/port_matrix_body.cc
index 847ee2f2ca..f448952c4a 100644
--- a/gtk2_ardour/port_matrix_body.cc
+++ b/gtk2_ardour/port_matrix_body.cc
@@ -246,10 +246,7 @@ PortMatrixBody::setup ()
 {
 	/* Discard any old connections to bundles */
 
-	for (list<sigc::connection>::iterator i = _bundle_connections.begin(); i != _bundle_connections.end(); ++i) {
-		i->disconnect ();
-	}
-	_bundle_connections.clear ();
+	_bundle_connections.drop_connections ();
 
 	/* Connect to bundles so that we find out when their names change */
 
@@ -257,9 +254,7 @@ PortMatrixBody::setup ()
 		PortGroup::BundleList r = _matrix->visible_rows()->bundles ();
 		for (PortGroup::BundleList::iterator i = r.begin(); i != r.end(); ++i) {
 			
-			_bundle_connections.push_back (
-				i->bundle->Changed.connect (sigc::hide (sigc::mem_fun (*this, &PortMatrixBody::rebuild_and_draw_row_labels)))
-				);
+			_bundle_connections.add_connection ((*i)->bundle->Changed.connect (boost::bind (&PortMatrixBody::rebuild_and_draw_row_labels, this)));
 			
 		}
 	}
@@ -267,9 +262,7 @@ PortMatrixBody::setup ()
 	if (_matrix->visible_columns()) {
 		PortGroup::BundleList c = _matrix->visible_columns()->bundles ();
 		for (PortGroup::BundleList::iterator i = c.begin(); i != c.end(); ++i) {
-			_bundle_connections.push_back (
-				i->bundle->Changed.connect (sigc::hide (sigc::mem_fun (*this, &PortMatrixBody::rebuild_and_draw_column_labels)))
-				);
+			_bundle_connections.add_connection ((*i)->bundle->Changed.connect (boost::bind (&PortMatrixBody::rebuild_and_draw_column_labels, this)));
 		}
 	}
 		
@@ -470,8 +463,8 @@ PortMatrixBody::highlight_associated_channels (int dim, ARDOUR::BundleChannel h)
 	PortGroup::BundleList const b = _matrix->visible_ports(1 - dim)->bundles ();
 
 	for (PortGroup::BundleList::const_iterator i = b.begin(); i != b.end(); ++i) {
-	        for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
-			bc[1 - dim] = ARDOUR::BundleChannel (i->bundle, j);
+	        for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
+			bc[1 - dim] = ARDOUR::BundleChannel ((*i)->bundle, j);
 			if (_matrix->get_state (bc) == PortMatrixNode::ASSOCIATED) {
 				if (dim == _matrix->column_index()) {
 					_row_labels->add_channel_highlight (bc[1 - dim]);
diff --git a/gtk2_ardour/port_matrix_body.h b/gtk2_ardour/port_matrix_body.h
index 0b8facda45..23d07c6ff3 100644
--- a/gtk2_ardour/port_matrix_body.h
+++ b/gtk2_ardour/port_matrix_body.h
@@ -104,7 +104,7 @@ private:
 	std::list<PortMatrixNode> _mouseover;
 	bool _ignore_component_size_changed;
 
-	std::list<sigc::connection> _bundle_connections;
+	PBD::ScopedConnectionList _bundle_connections;
 };
 
 #endif
diff --git a/gtk2_ardour/port_matrix_column_labels.cc b/gtk2_ardour/port_matrix_column_labels.cc
index be26474e75..522015548f 100644
--- a/gtk2_ardour/port_matrix_column_labels.cc
+++ b/gtk2_ardour/port_matrix_column_labels.cc
@@ -55,16 +55,16 @@ PortMatrixColumnLabels::compute_dimensions ()
 		for (PortGroup::BundleList::const_iterator j = c.begin (); j != c.end(); ++j) {
 
 			cairo_text_extents_t ext;
-			cairo_text_extents (cr, j->bundle->name().c_str(), &ext);
+			cairo_text_extents (cr, (*j)->bundle->name().c_str(), &ext);
 			if (ext.width > _longest_bundle_name) {
 				_longest_bundle_name = ext.width;
 			}
 
-			for (uint32_t k = 0; k < j->bundle->nchannels (); ++k) {
+			for (uint32_t k = 0; k < (*j)->bundle->nchannels (); ++k) {
 
 				cairo_text_extents (
 					cr,
-					j->bundle->channel_name (k).c_str(),
+					(*j)->bundle->channel_name (k).c_str(),
 					&ext
 					);
 
@@ -127,13 +127,13 @@ PortMatrixColumnLabels::render (cairo_t* cr)
 	PortGroup::BundleList const & bundles = _matrix->visible_columns()->bundles ();
 	for (PortGroup::BundleList::const_iterator i = bundles.begin (); i != bundles.end(); ++i) {
 
-		Gdk::Color c = i->has_colour ? i->colour : get_a_bundle_colour (N);
-		render_bundle_name (cr, background_colour (), c, x, 0, i->bundle);
+		Gdk::Color c = (*i)->has_colour ? (*i)->colour : get_a_bundle_colour (N);
+		render_bundle_name (cr, background_colour (), c, x, 0, (*i)->bundle);
 
 		if (_matrix->show_only_bundles()) {
 			x += grid_spacing();
 		} else {
-			x += i->bundle->nchannels () * grid_spacing();
+			x += (*i)->bundle->nchannels () * grid_spacing();
 		}
 		
 		++N;
@@ -147,9 +147,9 @@ PortMatrixColumnLabels::render (cairo_t* cr)
 
 		for (PortGroup::BundleList::const_iterator i = bundles.begin (); i != bundles.end(); ++i) {
 
-			for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
-				Gdk::Color c = i->has_colour ? i->colour : get_a_bundle_colour (N);
-				render_channel_name (cr, background_colour (), c, x, 0, ARDOUR::BundleChannel (i->bundle, j));
+			for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
+				Gdk::Color c = (*i)->has_colour ? (*i)->colour : get_a_bundle_colour (N);
+				render_channel_name (cr, background_colour (), c, x, 0, ARDOUR::BundleChannel ((*i)->bundle, j));
 				x += grid_spacing();
 			}
 			
diff --git a/gtk2_ardour/port_matrix_component.cc b/gtk2_ardour/port_matrix_component.cc
index d98c557c3a..f728f7bd85 100644
--- a/gtk2_ardour/port_matrix_component.cc
+++ b/gtk2_ardour/port_matrix_component.cc
@@ -131,7 +131,7 @@ PortMatrixComponent::group_size (boost::shared_ptr<const PortGroup> g) const
 		s = bundles.size();
 	} else {
 		for (PortGroup::BundleList::const_iterator i = bundles.begin(); i != bundles.end(); ++i) {
-			s += i->bundle->nchannels();
+			s += (*i)->bundle->nchannels();
 		}
 	}
 
@@ -151,7 +151,7 @@ PortMatrixComponent::channel_to_position (ARDOUR::BundleChannel bc, boost::share
 
 	for (PortGroup::BundleList::const_iterator i = bundles.begin(); i != bundles.end(); ++i) {
 
-		if (i->bundle == bc.bundle) {
+		if ((*i)->bundle == bc.bundle) {
 
 			/* found the bundle */
 			
@@ -168,7 +168,7 @@ PortMatrixComponent::channel_to_position (ARDOUR::BundleChannel bc, boost::share
 		if (_matrix->show_only_bundles()) {
 			p += 1;
 		} else {
-			p += i->bundle->nchannels ();
+			p += (*i)->bundle->nchannels ();
 		}
 	}
 
@@ -187,16 +187,16 @@ PortMatrixComponent::position_to_channel (double p, double, boost::shared_ptr<co
 		if (_matrix->show_only_bundles()) {
 			
 			if (p < 1) {
-				return ARDOUR::BundleChannel (j->bundle, -1);
+				return ARDOUR::BundleChannel ((*j)->bundle, -1);
 			} else {
 				p -= 1;
 			}
 			
 		} else {
 			
-			uint32_t const s = j->bundle->nchannels ();
+			uint32_t const s = (*j)->bundle->nchannels ();
 			if (p < s) {
-				return ARDOUR::BundleChannel (j->bundle, p);
+				return ARDOUR::BundleChannel ((*j)->bundle, p);
 			} else {
 				p -= s;
 			}
diff --git a/gtk2_ardour/port_matrix_grid.cc b/gtk2_ardour/port_matrix_grid.cc
index 3e5d171690..fdfe45b224 100644
--- a/gtk2_ardour/port_matrix_grid.cc
+++ b/gtk2_ardour/port_matrix_grid.cc
@@ -81,7 +81,7 @@ PortMatrixGrid::render (cairo_t* cr)
 
 		if (!_matrix->show_only_bundles()) {
 			cairo_set_line_width (cr, thin_grid_line_width());
-			for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
+			for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
 				x += grid_spacing ();
 				cairo_move_to (cr, x, 0);
 				cairo_line_to (cr, x, _height);
@@ -111,7 +111,7 @@ PortMatrixGrid::render (cairo_t* cr)
 
 		if (!_matrix->show_only_bundles()) {
 			cairo_set_line_width (cr, thin_grid_line_width());
-			for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
+			for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
 				y += grid_spacing ();
 				cairo_move_to (cr, 0, y);
 				cairo_line_to (cr, _width, y);
@@ -140,8 +140,8 @@ PortMatrixGrid::render (cairo_t* cr)
 			for (PortGroup::BundleList::const_iterator j = row_bundles.begin(); j != row_bundles.end(); ++j) {
 
 				PortMatrixNode::State s = get_association (PortMatrixNode (
-										   ARDOUR::BundleChannel (i->bundle, 0),
-										   ARDOUR::BundleChannel (j->bundle, 0)
+										   ARDOUR::BundleChannel ((*i)->bundle, 0),
+										   ARDOUR::BundleChannel ((*j)->bundle, 0)
 										   ));
 				switch (s) {
 				case PortMatrixNode::ASSOCIATED:
@@ -169,14 +169,14 @@ PortMatrixGrid::render (cairo_t* cr)
 			for (PortGroup::BundleList::const_iterator j = row_bundles.begin(); j != row_bundles.end(); ++j) {
 
 				x = bx;
-				for (uint32_t k = 0; k < i->bundle->nchannels (); ++k) {
+				for (uint32_t k = 0; k < (*i)->bundle->nchannels (); ++k) {
 
 					y = by;
-					for (uint32_t l = 0; l < j->bundle->nchannels (); ++l) {
+					for (uint32_t l = 0; l < (*j)->bundle->nchannels (); ++l) {
 
 						ARDOUR::BundleChannel c[2];
-						c[_matrix->column_index()] = ARDOUR::BundleChannel (i->bundle, k);
-						c[_matrix->row_index()] = ARDOUR::BundleChannel (j->bundle, l);
+						c[_matrix->column_index()] = ARDOUR::BundleChannel ((*i)->bundle, k);
+						c[_matrix->row_index()] = ARDOUR::BundleChannel ((*j)->bundle, l);
 
 						PortMatrixNode::State const s = _matrix->get_state (c);
 
@@ -198,10 +198,10 @@ PortMatrixGrid::render (cairo_t* cr)
 					x += grid_spacing();
 				}
 
-				by += j->bundle->nchannels () * grid_spacing();
+				by += (*j)->bundle->nchannels () * grid_spacing();
 			}
 
-			bx += i->bundle->nchannels () * grid_spacing();
+			bx += (*i)->bundle->nchannels () * grid_spacing();
 		}
 	}
 }
diff --git a/gtk2_ardour/port_matrix_row_labels.cc b/gtk2_ardour/port_matrix_row_labels.cc
index 80a0bb0c4f..2bf2b70a27 100644
--- a/gtk2_ardour/port_matrix_row_labels.cc
+++ b/gtk2_ardour/port_matrix_row_labels.cc
@@ -54,16 +54,16 @@ PortMatrixRowLabels::compute_dimensions ()
 		PortGroup::BundleList const r = (*i)->bundles ();
 		for (PortGroup::BundleList::const_iterator j = r.begin(); j != r.end(); ++j) {
 
-			for (uint32_t k = 0; k < j->bundle->nchannels(); ++k) {
+			for (uint32_t k = 0; k < (*j)->bundle->nchannels(); ++k) {
 				cairo_text_extents_t ext;
-				cairo_text_extents (cr, j->bundle->channel_name(k).c_str(), &ext);
+				cairo_text_extents (cr, (*j)->bundle->channel_name(k).c_str(), &ext);
 				if (ext.width > _longest_port_name) {
 					_longest_port_name = ext.width;
 				}
 			}
 
 			cairo_text_extents_t ext;
-			cairo_text_extents (cr, j->bundle->name().c_str(), &ext);
+			cairo_text_extents (cr, (*j)->bundle->name().c_str(), &ext);
 			if (ext.width > _longest_bundle_name) {
 				_longest_bundle_name = ext.width;
 			}
@@ -107,12 +107,12 @@ PortMatrixRowLabels::render (cairo_t* cr)
 	
 	PortGroup::BundleList const & bundles = _matrix->visible_rows()->bundles ();
 	for (PortGroup::BundleList::const_iterator i = bundles.begin(); i != bundles.end(); ++i) {
-		render_bundle_name (cr, background_colour (), i->has_colour ? i->colour : get_a_bundle_colour (N), 0, y, i->bundle);
+		render_bundle_name (cr, background_colour (), (*i)->has_colour ? (*i)->colour : get_a_bundle_colour (N), 0, y, (*i)->bundle);
 
 		if (!_matrix->show_only_bundles()) {
-			for (uint32_t j = 0; j < i->bundle->nchannels(); ++j) {
-				Gdk::Color c = i->has_colour ? i->colour : get_a_bundle_colour (M);
-				render_channel_name (cr, background_colour (), c, 0, y, ARDOUR::BundleChannel (i->bundle, j));
+			for (uint32_t j = 0; j < (*i)->bundle->nchannels(); ++j) {
+				Gdk::Color c = (*i)->has_colour ? (*i)->colour : get_a_bundle_colour (M);
+				render_channel_name (cr, background_colour (), c, 0, y, ARDOUR::BundleChannel ((*i)->bundle, j));
 				y += grid_spacing();
 				++M;
 			}
diff --git a/gtk2_ardour/processor_box.cc b/gtk2_ardour/processor_box.cc
index ab6d9f546d..3e07305868 100644
--- a/gtk2_ardour/processor_box.cc
+++ b/gtk2_ardour/processor_box.cc
@@ -270,16 +270,17 @@ SendProcessorEntry::set_pixel_width (int p)
 	_fader.set_fader_length (p);
 }
 
-ProcessorBox::ProcessorBox (ARDOUR::Session& sess, sigc::slot<PluginSelector*> get_plugin_selector,
-			RouteRedirectSelection& rsel, MixerStrip* parent, bool owner_is_mixer)
-	: _session(sess)
-	, _parent_strip (parent)
+ProcessorBox::ProcessorBox (ARDOUR::Session* sess, boost::function<PluginSelector*()> get_plugin_selector,
+			    RouteRedirectSelection& rsel, MixerStrip* parent, bool owner_is_mixer)
+	: _parent_strip (parent)
 	, _owner_is_mixer (owner_is_mixer)
 	, ab_direction (true)
 	, _get_plugin_selector (get_plugin_selector)
 	, _placement(PreFader)
 	, _rr_selection(rsel)
 {
+	set_session (sess);
+
 	_width = Wide;
 	processor_menu = 0;
 	send_action_menu = 0;
@@ -319,17 +320,15 @@ ProcessorBox::set_route (boost::shared_ptr<Route> r)
 		return;
 	}
 	
-	connections.clear ();
+	connections.drop_connections();
 
 	/* new route: any existing block on processor redisplay must be meaningless */
 	no_processor_redisplay = false;
 	_route = r;
 
-	connections.push_back (_route->processors_changed.connect (sigc::mem_fun (*this, &ProcessorBox::route_processors_changed)));
-	connections.push_back (_route->GoingAway.connect (
-			sigc::mem_fun (*this, &ProcessorBox::route_going_away)));
-	connections.push_back (_route->NameChanged.connect (
-			sigc::mem_fun(*this, &ProcessorBox::route_name_changed)));
+	connections.add_connection (_route->processors_changed.connect (sigc::mem_fun (*this, &ProcessorBox::route_processors_changed)));
+	connections.add_connection (_route->GoingAway.connect (sigc::mem_fun (*this, &ProcessorBox::route_going_away)));
+	connections.add_connection (_route->NameChanged.connect (sigc::mem_fun(*this, &ProcessorBox::route_name_changed)));
 
 	redisplay_processors ();
 }
@@ -437,7 +436,7 @@ ProcessorBox::build_send_action_menu ()
 Gtk::Menu*
 ProcessorBox::build_possible_aux_menu ()
 {
-	boost::shared_ptr<RouteList> rl = _session.get_routes_with_internal_returns();
+	boost::shared_ptr<RouteList> rl = _session->get_routes_with_internal_returns();
 
 	if (rl->empty()) {
 		return 0;
@@ -630,7 +629,7 @@ ProcessorBox::processor_button_press_event (GdkEventButton *ev, ProcessorEntry*
 
 	if (processor && (Keyboard::is_edit_event (ev) || (ev->button == 1 && ev->type == GDK_2BUTTON_PRESS))) {
 
-		if (_session.engine().connected()) {
+		if (_session->engine().connected()) {
 			/* XXX giving an error message here is hard, because we may be in the midst of a button press */
 			edit_processor (processor);
 		}
@@ -747,7 +746,7 @@ ProcessorBox::use_plugins (const SelectedPlugins& plugins)
 {
 	for (SelectedPlugins::const_iterator p = plugins.begin(); p != plugins.end(); ++p) {
 
-		boost::shared_ptr<Processor> processor (new PluginInsert (_session, *p));
+		boost::shared_ptr<Processor> processor (new PluginInsert (*_session, *p));
 
 		Route::ProcessorStreams err_streams;
 
@@ -812,18 +811,18 @@ ProcessorBox::weird_plugin_dialog (Plugin& p, Route::ProcessorStreams streams)
 void
 ProcessorBox::choose_insert ()
 {
-	boost::shared_ptr<Processor> processor (new PortInsert (_session, _route->mute_master()));
+	boost::shared_ptr<Processor> processor (new PortInsert (*_session, _route->mute_master()));
 	_route->add_processor (processor, _placement);
 }
 
 void
 ProcessorBox::choose_send ()
 {
-	boost::shared_ptr<Send> send (new Send (_session, _route->mute_master()));
+	boost::shared_ptr<Send> send (new Send (*_session, _route->mute_master()));
 
 	/* make an educated guess at the initial number of outputs for the send */
-	ChanCount outs = (_session.master_out())
-			? _session.master_out()->n_outputs()
+	ChanCount outs = (_session->master_out())
+			? _session->master_out()->n_outputs()
 			: _route->n_outputs();
 
 	/* XXX need processor lock on route */
@@ -841,7 +840,7 @@ ProcessorBox::choose_send ()
 	   is closed.
 	 */
 
-	IOSelectorWindow *ios = new IOSelectorWindow (&_session, send->output(), true);
+	IOSelectorWindow *ios = new IOSelectorWindow (_session, send->output(), true);
 	ios->show_all ();
 
 	/* keep a reference to the send so it doesn't get deleted while
@@ -927,7 +926,7 @@ ProcessorBox::choose_aux (boost::weak_ptr<Route> wr)
 	boost::shared_ptr<RouteList> rlist (new RouteList);
 	rlist->push_back (_route);
 
-	_session.add_internal_sends (target, PreFader, rlist);
+	_session->add_internal_sends (target, PreFader, rlist);
 }
 
 void
@@ -1219,7 +1218,7 @@ ProcessorBox::rename_processor (boost::shared_ptr<Processor> processor)
 	case Gtk::RESPONSE_ACCEPT:
 		name_prompter.get_result (result);
 		if (result.length()) {
-			if (_session.route_by_name (result)) {
+			if (_session->route_by_name (result)) {
 				ARDOUR_UI::instance()->popup_error (_("A track already exists with that name."));
 				return;
 			}
@@ -1279,20 +1278,20 @@ ProcessorBox::paste_processor_state (const XMLNodeList& nlist, boost::shared_ptr
 			} else if (type->value() == "send") {
 
 				XMLNode n (**niter);
-				Send::make_unique (n, _session);
-				p.reset (new Send (_session, _route->mute_master(), n));
+				Send::make_unique (n, *_session);
+				p.reset (new Send (*_session, _route->mute_master(), n));
 
 			} else if (type->value() == "return") {
 
 				XMLNode n (**niter);
-				Return::make_unique (n, _session);
-				p.reset (new Return (_session, **niter));
+				Return::make_unique (n, *_session);
+				p.reset (new Return (*_session, **niter));
 
 			} else {
 				/* XXX its a bit limiting to assume that everything else
 				   is a plugin.
 				*/
-				p.reset (new PluginInsert (_session, **niter));
+				p.reset (new PluginInsert (*_session, **niter));
 			}
 
 			copies.push_back (p);
@@ -1424,7 +1423,7 @@ ProcessorBox::edit_processor (boost::shared_ptr<Processor> processor)
 
 	if ((send = boost::dynamic_pointer_cast<Send> (processor)) != 0) {
 
-		if (!_session.engine().connected()) {
+		if (!_session->engine().connected()) {
 			return;
 		}
 
@@ -1449,7 +1448,7 @@ ProcessorBox::edit_processor (boost::shared_ptr<Processor> processor)
 
 	} else if ((retrn = boost::dynamic_pointer_cast<Return> (processor)) != 0) {
 
-		if (!_session.engine().connected()) {
+		if (!_session->engine().connected()) {
 			return;
 		}
 
@@ -1493,7 +1492,7 @@ ProcessorBox::edit_processor (boost::shared_ptr<Processor> processor)
 
 	} else if ((port_insert = boost::dynamic_pointer_cast<PortInsert> (processor)) != 0) {
 
-		if (!_session.engine().connected()) {
+		if (!_session->engine().connected()) {
 			MessageDialog msg ( _("Not connected to JACK - no I/O changes are possible"));
 			msg.run ();
 			return;
@@ -1502,7 +1501,7 @@ ProcessorBox::edit_processor (boost::shared_ptr<Processor> processor)
 		PortInsertWindow *io_selector;
 
 		if (port_insert->get_gui() == 0) {
-			io_selector = new PortInsertWindow (&_session, port_insert);
+			io_selector = new PortInsertWindow (_session, port_insert);
 			port_insert->set_gui (io_selector);
 
 		} else {
diff --git a/gtk2_ardour/processor_box.h b/gtk2_ardour/processor_box.h
index daff50dfe7..e704eba015 100644
--- a/gtk2_ardour/processor_box.h
+++ b/gtk2_ardour/processor_box.h
@@ -20,9 +20,11 @@
 #ifndef __ardour_gtk_processor_box__
 #define __ardour_gtk_processor_box__
 
+#include <cmath>
 #include <vector>
 
-#include <cmath>
+#include <boost/function.hpp>
+
 #include <gtkmm/box.h>
 #include <gtkmm/eventbox.h>
 #include <gtkmm/menu.h>
@@ -34,6 +36,7 @@
 #include <gtkmm2ext/pixfader.h>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/types.h"
 #include "ardour/ardour.h"
@@ -41,6 +44,7 @@
 #include "ardour/port_insert.h"
 #include "ardour/processor.h"
 #include "ardour/route.h"
+#include "ardour/session_handle.h"
 
 #include "pbd/fastlog.h"
 
@@ -120,11 +124,11 @@ private:
 	static Glib::RefPtr<Gdk::Pixbuf> _slider;
 };
 
-class ProcessorBox : public Gtk::HBox, public PluginInterestedObject
+class ProcessorBox : public Gtk::HBox, public PluginInterestedObject, public ARDOUR::SessionHandlePtr
 {
   public:
-	ProcessorBox (ARDOUR::Session&, sigc::slot<PluginSelector*> get_plugin_selector,
-			RouteRedirectSelection&, MixerStrip* parent, bool owner_is_mixer = false);
+	ProcessorBox (ARDOUR::Session*, boost::function<PluginSelector*()> get_plugin_selector,
+		      RouteRedirectSelection&, MixerStrip* parent, bool owner_is_mixer = false);
 	~ProcessorBox ();
 
 	void set_route (boost::shared_ptr<ARDOUR::Route>);
@@ -145,13 +149,12 @@ class ProcessorBox : public Gtk::HBox, public PluginInterestedObject
 
   private:
 	boost::shared_ptr<ARDOUR::Route>  _route;
-	ARDOUR::Session &   _session;
 	MixerStrip*         _parent_strip; // null if in RouteParamsUI
 	bool                _owner_is_mixer;
 	bool                 ab_direction;
-	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList connections;
 
-	sigc::slot<PluginSelector*> _get_plugin_selector;
+	boost::function<PluginSelector*()> _get_plugin_selector;
 
 	boost::shared_ptr<ARDOUR::Processor> _processor_being_created;
 
diff --git a/gtk2_ardour/public_editor.h b/gtk2_ardour/public_editor.h
index 8b4684f539..1677c2ee49 100644
--- a/gtk2_ardour/public_editor.h
+++ b/gtk2_ardour/public_editor.h
@@ -83,7 +83,7 @@ class MarkerView;
  * of PublicEditor need not be recompiled if private methods or member variables
  * change.
  */
-class PublicEditor : public Gtk::Window, public PBD::StatefulThingWithGoingAway {
+class PublicEditor : public Gtk::Window, public PBD::StatefulDestructible {
   public:
 	PublicEditor ();
 	virtual ~PublicEditor ();
@@ -97,10 +97,10 @@ class PublicEditor : public Gtk::Window, public PBD::StatefulThingWithGoingAway
 	/** Attach this editor to a Session.
 	 * @param s Session to connect to.
 	 */
-	virtual void connect_to_session (ARDOUR::Session* s) = 0;
+	virtual void set_session (ARDOUR::Session* s) = 0;
 
 	/** @return The Session that we are editing, or 0 */
-	virtual ARDOUR::Session* current_session () const = 0;
+	virtual ARDOUR::Session* session () const = 0;
 
 	/** Set the snap type.
 	 * @param t Snap type (defined in editing_syms.h)
diff --git a/gtk2_ardour/region_editor.h b/gtk2_ardour/region_editor.h
index 596bd44140..f66d7f8f81 100644
--- a/gtk2_ardour/region_editor.h
+++ b/gtk2_ardour/region_editor.h
@@ -20,6 +20,8 @@
 #ifndef __gtk_ardour_region_edit_h__
 #define __gtk_ardour_region_edit_h__
 
+#include "ardour/session_handle.h"
+
 #include "ardour_dialog.h"
 
 namespace ARDOUR { class Session; }
@@ -28,15 +30,12 @@ namespace ARDOUR { class Session; }
 class RegionEditor : public ArdourDialog
 {
   public:
-	RegionEditor(ARDOUR::Session& s)
-	: ArdourDialog ("region editor")
-	, _session(s)
-	{}
+	RegionEditor(ARDOUR::Session* s)
+		: ArdourDialog ("region editor") {
+		set_session (s);
+	}
 
 	virtual ~RegionEditor () {}
-
-  protected:
-	ARDOUR::Session&     _session;
 };
 
 #endif /* __gtk_ardour_region_edit_h__ */
diff --git a/gtk2_ardour/region_gain_line.cc b/gtk2_ardour/region_gain_line.cc
index b3dea4f42a..00352c96df 100644
--- a/gtk2_ardour/region_gain_line.cc
+++ b/gtk2_ardour/region_gain_line.cc
@@ -18,9 +18,11 @@
 */
 
 #include "evoral/Curve.hpp"
-#include "ardour/audioregion.h"
 #include "pbd/memento_command.h"
 
+#include "ardour/audioregion.h"
+#include "ardour/session.h"
+
 #include "region_gain_line.h"
 #include "audio_region_view.h"
 #include "utils.h"
@@ -28,17 +30,14 @@
 #include "time_axis_view.h"
 #include "editor.h"
 
-#include "ardour/session.h"
-
 #include "i18n.h"
 
 using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-AudioRegionGainLine::AudioRegionGainLine (const string & name, Session& s, AudioRegionView& r, ArdourCanvas::Group& parent, boost::shared_ptr<AutomationList> l)
+AudioRegionGainLine::AudioRegionGainLine (const string & name, AudioRegionView& r, ArdourCanvas::Group& parent, boost::shared_ptr<AutomationList> l)
 	: AutomationLine (name, r.get_time_axis_view(), parent, l)
-	, session (s)
 	, rv (r)
 {
 	// If this isn't true something is horribly wrong, and we'll get catastrophic gain values
@@ -55,7 +54,7 @@ AudioRegionGainLine::start_drag (ControlPoint* cp, nframes_t x, float fraction)
 {
 	AutomationLine::start_drag (cp, x, fraction);
 	if (!rv.audio_region()->envelope_active()) {
-		trackview.session().add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), &rv.audio_region()->get_state(), 0));
+		trackview.session()->add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), &rv.audio_region()->get_state(), 0));
 		rv.audio_region()->set_envelope_active(false);
 	}
 }
@@ -68,21 +67,21 @@ AudioRegionGainLine::remove_point (ControlPoint& cp)
 
 	model_representation (cp, mr);
 
-	trackview.editor().current_session()->begin_reversible_command (_("remove control point"));
+	trackview.editor().session()->begin_reversible_command (_("remove control point"));
 	XMLNode &before = alist->get_state();
 
 	if (!rv.audio_region()->envelope_active()) {
 		XMLNode &region_before = rv.audio_region()->get_state();
 		rv.audio_region()->set_envelope_active(true);
 		XMLNode &region_after = rv.audio_region()->get_state();
-		trackview.session().add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), &region_before, &region_after));
+		trackview.session()->add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), &region_before, &region_after));
 	}
 
 	alist->erase (mr.start, mr.end);
 
-	trackview.editor().current_session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
-	trackview.editor().current_session()->commit_reversible_command ();
-	trackview.editor().current_session()->set_dirty ();
+	trackview.editor().session()->add_command (new MementoCommand<AutomationList>(*alist.get(), &before, &alist->get_state()));
+	trackview.editor().session()->commit_reversible_command ();
+	trackview.editor().session()->set_dirty ();
 }
 
 void
@@ -90,7 +89,7 @@ AudioRegionGainLine::end_drag (ControlPoint* cp)
 {
 	if (!rv.audio_region()->envelope_active()) {
 		rv.audio_region()->set_envelope_active(true);
-		trackview.session().add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), 0, &rv.audio_region()->get_state()));
+		trackview.session()->add_command(new MementoCommand<AudioRegion>(*(rv.audio_region().get()), 0, &rv.audio_region()->get_state()));
 	}
 
 	AutomationLine::end_drag(cp);
diff --git a/gtk2_ardour/region_gain_line.h b/gtk2_ardour/region_gain_line.h
index 7033c65604..d54c962294 100644
--- a/gtk2_ardour/region_gain_line.h
+++ b/gtk2_ardour/region_gain_line.h
@@ -21,6 +21,7 @@
 #define __ardour_gtk_region_gain_line_h__
 
 #include "ardour/ardour.h"
+
 #include <libgnomecanvasmm.h>
 
 #include "automation_line.h"
@@ -35,7 +36,7 @@ class AudioRegionView;
 class AudioRegionGainLine : public AutomationLine
 {
   public:
-	AudioRegionGainLine (const std::string & name, ARDOUR::Session&, AudioRegionView&, ArdourCanvas::Group& parent, boost::shared_ptr<ARDOUR::AutomationList>);
+	AudioRegionGainLine (const std::string & name, AudioRegionView&, ArdourCanvas::Group& parent, boost::shared_ptr<ARDOUR::AutomationList>);
 
 	void start_drag (ControlPoint*, nframes_t x, float fraction);
 	void end_drag (ControlPoint*);
@@ -43,7 +44,6 @@ class AudioRegionGainLine : public AutomationLine
 	void remove_point (ControlPoint&);
 
   private:
-	ARDOUR::Session& session;
 	AudioRegionView& rv;
 };
 
diff --git a/gtk2_ardour/region_selection.cc b/gtk2_ardour/region_selection.cc
index 94592000a1..30f6dfb565 100644
--- a/gtk2_ardour/region_selection.cc
+++ b/gtk2_ardour/region_selection.cc
@@ -32,7 +32,7 @@ using namespace PBD;
  */
 RegionSelection::RegionSelection ()
 {
-	RegionView::RegionViewGoingAway.connect (sigc::mem_fun(*this, &RegionSelection::remove_it));
+	death_connection = RegionView::RegionViewGoingAway.connect (boost::bind (&RegionSelection::remove_it, this, _1));
 
 	_current_start = 0;
 	_current_end = 0;
@@ -43,9 +43,8 @@ RegionSelection::RegionSelection ()
  */
 RegionSelection::RegionSelection (const RegionSelection& other)
 	: std::list<RegionView*>()
-	, sigc::trackable(other)
 {
-	RegionView::RegionViewGoingAway.connect (sigc::mem_fun(*this, &RegionSelection::remove_it));
+	death_connection = RegionView::RegionViewGoingAway.connect (boost::bind (&RegionSelection::remove_it, this, _1));
 
 	_current_start = other._current_start;
 	_current_end = other._current_end;
diff --git a/gtk2_ardour/region_selection.h b/gtk2_ardour/region_selection.h
index f89eef9eb8..dcb6d68e0c 100644
--- a/gtk2_ardour/region_selection.h
+++ b/gtk2_ardour/region_selection.h
@@ -21,7 +21,9 @@
 
 #include <set>
 #include <list>
-#include <sigc++/signal.h>
+
+#include <boost/signals2.hpp>
+
 #include "ardour/types.h"
 
 class RegionView;
@@ -29,7 +31,7 @@ class TimeAxisView;
 
 /** Class to represent list of selected regions.
  */
-class RegionSelection : public std::list<RegionView*>, public sigc::trackable
+class RegionSelection : public std::list<RegionView*>
 {
   public:
 	RegionSelection();
@@ -69,6 +71,7 @@ class RegionSelection : public std::list<RegionView*>, public sigc::trackable
 	nframes_t _current_end; ///< end position for the selection
 
 	std::list<RegionView *> _bylayer; ///< list of regions sorted by layer
+	boost::signals2::scoped_connection death_connection;
 };
 
 #endif /* __ardour_gtk_region_selection_h__ */
diff --git a/gtk2_ardour/region_view.cc b/gtk2_ardour/region_view.cc
index 343c2b47ff..5cc4df5669 100644
--- a/gtk2_ardour/region_view.cc
+++ b/gtk2_ardour/region_view.cc
@@ -58,7 +58,7 @@ using namespace ArdourCanvas;
 
 static const int32_t sync_mark_width = 9;
 
-sigc::signal<void,RegionView*> RegionView::RegionViewGoingAway;
+boost::signals2::signal<void(RegionView*)> RegionView::RegionViewGoingAway;
 
 RegionView::RegionView (ArdourCanvas::Group*              parent,
                         TimeAxisView&                     tv,
diff --git a/gtk2_ardour/region_view.h b/gtk2_ardour/region_view.h
index 288969616f..ad534c04bf 100644
--- a/gtk2_ardour/region_view.h
+++ b/gtk2_ardour/region_view.h
@@ -89,7 +89,7 @@ class RegionView : public TimeAxisViewItem
 	void enable_display(bool yn) { _enable_display = yn; }
 	virtual void update_coverage_frames (LayerDisplay);
 
-	static sigc::signal<void,RegionView*> RegionViewGoingAway;
+	static boost::signals2::signal<void(RegionView*)> RegionViewGoingAway;
 
   protected:
 
@@ -139,7 +139,7 @@ class RegionView : public TimeAxisViewItem
     bool    in_destructor;
 
     bool             wait_for_data;
-    sigc::connection data_ready_connection;
+    boost::signals2::scoped_connection data_ready_connection;
 
     std::vector<GhostRegion*> ghosts;
 
diff --git a/gtk2_ardour/return_ui.cc b/gtk2_ardour/return_ui.cc
index c4a4472553..8a12a3ece9 100644
--- a/gtk2_ardour/return_ui.cc
+++ b/gtk2_ardour/return_ui.cc
@@ -34,10 +34,9 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-ReturnUI::ReturnUI (Gtk::Window* parent, boost::shared_ptr<Return> r, Session& se)
-	: _return (r)
-	, _session (se)
-	, _gpm (se, 250)
+ReturnUI::ReturnUI (Gtk::Window* parent, boost::shared_ptr<Return> r, Session* session)
+	:_return (r)
+	, _gpm (session, 250)
 {
  	_gpm.set_controls (boost::shared_ptr<Route>(), r->meter(), r->amp());
 
@@ -49,7 +48,7 @@ ReturnUI::ReturnUI (Gtk::Window* parent, boost::shared_ptr<Return> r, Session& s
 
 	_vbox.pack_start (_hbox, false, false, false);
 
-	io = manage (new IOSelector (parent, &se, r->output()));
+	io = manage (new IOSelector (parent, session, r->output()));
 
 	pack_start (_vbox, false, false);
 
@@ -99,10 +98,10 @@ ReturnUI::fast_update ()
 	}
 }
 
-ReturnUIWindow::ReturnUIWindow (boost::shared_ptr<Return> s, Session& ss)
-	: ArdourDialog (string("Ardour: return ") + s->name())
+ReturnUIWindow::ReturnUIWindow (boost::shared_ptr<Return> r, ARDOUR::Session* s)
+	: ArdourDialog (string("Ardour: return ") + r->name())
 {
-	ui = new ReturnUI (this, s, ss);
+	ui = new ReturnUI (this, r, s);
 
 	hpacker.pack_start (*ui, true, true);
 
@@ -111,7 +110,7 @@ ReturnUIWindow::ReturnUIWindow (boost::shared_ptr<Return> s, Session& ss)
 
 	set_name ("ReturnUIWindow");
 
-	going_away_connection = s->GoingAway.connect (sigc::mem_fun (*this, &ReturnUIWindow::return_going_away));
+	going_away_connection = r->GoingAway.connect (sigc::mem_fun (*this, &ReturnUIWindow::return_going_away));
 	signal_delete_event().connect (sigc::bind (sigc::ptr_fun (just_hide_it), reinterpret_cast<Window *> (this)));
 }
 
@@ -124,7 +123,7 @@ void
 ReturnUIWindow::return_going_away ()
 {
 	ENSURE_GUI_THREAD (*this, &ReturnUIWindow::return_going_away)
+	going_away_connection.disconnect ();	
 	delete_when_idle (this);
-	going_away_connection.disconnect ();
 }
 
diff --git a/gtk2_ardour/return_ui.h b/gtk2_ardour/return_ui.h
index 3a5e3c8f3f..ff1f2f35e5 100644
--- a/gtk2_ardour/return_ui.h
+++ b/gtk2_ardour/return_ui.h
@@ -26,16 +26,15 @@
 
 namespace ARDOUR {
 	class Return;
-	class Session;
 	class IOProcessor;
 }
 
 class IOSelector;
 
-class ReturnUI : public Gtk::HBox
+class ReturnUI : public Gtk::HBox 
 {
   public:
-	ReturnUI (Gtk::Window *,boost::shared_ptr<ARDOUR::Return>, ARDOUR::Session&);
+	ReturnUI (Gtk::Window *,boost::shared_ptr<ARDOUR::Return>, ARDOUR::Session*);
 	~ReturnUI();
 
 	void update ();
@@ -47,7 +46,6 @@ class ReturnUI : public Gtk::HBox
 
   private:
 	boost::shared_ptr<ARDOUR::Return> _return;
-	ARDOUR::Session&                  _session;
 	GainMeter                         _gpm;
 	Gtk::VBox                         _vbox;
 	Gtk::VBox                         _hbox;
@@ -61,7 +59,7 @@ class ReturnUI : public Gtk::HBox
 class ReturnUIWindow : public ArdourDialog
 {
   public:
-	ReturnUIWindow(boost::shared_ptr<ARDOUR::Return>, ARDOUR::Session&);
+	ReturnUIWindow(boost::shared_ptr<ARDOUR::Return>, ARDOUR::Session*);
 	~ReturnUIWindow();
 
 	ReturnUI* ui;
@@ -70,7 +68,7 @@ class ReturnUIWindow : public ArdourDialog
 	Gtk::HBox hpacker;
 
 	void return_going_away ();
-	sigc::connection going_away_connection;
+	boost::signals2::scoped_connection going_away_connection;
 };
 
 #endif /* __ardour_gtk_return_ui_h__ */
diff --git a/gtk2_ardour/rhythm_ferret.cc b/gtk2_ardour/rhythm_ferret.cc
index 1f38bb8992..f6619fcb8b 100644
--- a/gtk2_ardour/rhythm_ferret.cc
+++ b/gtk2_ardour/rhythm_ferret.cc
@@ -230,7 +230,7 @@ RhythmFerret::get_action () const
 void
 RhythmFerret::run_analysis ()
 {
-	if (!session) {
+	if (!_session) {
 		return;
 	}
 
@@ -268,7 +268,7 @@ RhythmFerret::run_analysis ()
 int
 RhythmFerret::run_percussion_onset_analysis (boost::shared_ptr<Readable> readable, nframes64_t offset, AnalysisFeatureList& results)
 {
-	TransientDetector t (session->frame_rate());
+	TransientDetector t (_session->frame_rate());
 
 	for (uint32_t i = 0; i < readable->n_channels(); ++i) {
 
@@ -295,7 +295,7 @@ RhythmFerret::run_percussion_onset_analysis (boost::shared_ptr<Readable> readabl
 	}
 
 	if (!results.empty()) {
-		TransientDetector::cleanup_transients (results, session->frame_rate(), trigger_gap_adjustment.get_value());
+		TransientDetector::cleanup_transients (results, _session->frame_rate(), trigger_gap_adjustment.get_value());
 	}
 
 	return 0;
@@ -322,7 +322,7 @@ int
 RhythmFerret::run_note_onset_analysis (boost::shared_ptr<Readable> readable, nframes64_t offset, AnalysisFeatureList& results)
 {
 	try {
-		OnsetDetector t (session->frame_rate());
+		OnsetDetector t (_session->frame_rate());
 
 		for (uint32_t i = 0; i < readable->n_channels(); ++i) {
 
@@ -356,7 +356,7 @@ RhythmFerret::run_note_onset_analysis (boost::shared_ptr<Readable> readable, nfr
 	}
 
 	if (!results.empty()) {
-		OnsetDetector::cleanup_onsets (results, session->frame_rate(), trigger_gap_adjustment.get_value());
+		OnsetDetector::cleanup_onsets (results, _session->frame_rate(), trigger_gap_adjustment.get_value());
 	}
 
 	return 0;
@@ -365,7 +365,7 @@ RhythmFerret::run_note_onset_analysis (boost::shared_ptr<Readable> readable, nfr
 void
 RhythmFerret::do_action ()
 {
-	if (!session || current_results.empty()) {
+	if (!_session || current_results.empty()) {
 		return;
 	}
 
@@ -390,7 +390,7 @@ RhythmFerret::do_split_action ()
 		return;
 	}
 
-	session->begin_reversible_command (_("split regions (rhythm ferret)"));
+	_session->begin_reversible_command (_("split regions (rhythm ferret)"));
 
 	for (RegionSelection::iterator i = regions.begin(); i != regions.end(); ) {
 
@@ -408,7 +408,7 @@ RhythmFerret::do_split_action ()
 		i = tmp;
 	}
 
-	session->commit_reversible_command ();
+	_session->commit_reversible_command ();
 }
 
 void
diff --git a/gtk2_ardour/route_group_menu.cc b/gtk2_ardour/route_group_menu.cc
index 08d2312415..7e05c26fe3 100644
--- a/gtk2_ardour/route_group_menu.cc
+++ b/gtk2_ardour/route_group_menu.cc
@@ -28,9 +28,9 @@
 using namespace Gtk;
 using namespace ARDOUR;
 
-RouteGroupMenu::RouteGroupMenu (Session& s, RouteGroup::Property p)
-	: _session (s),
-	  _default_properties (p)
+RouteGroupMenu::RouteGroupMenu (Session* s, RouteGroup::Property p)
+	: SessionHandlePtr (s)
+	, _default_properties (p)
 {
 	rebuild (0);
 }
@@ -52,7 +52,9 @@ RouteGroupMenu::rebuild (RouteGroup* curr)
 		static_cast<RadioMenuItem*> (&items().back())->set_active ();
 	}
 
-	_session.foreach_route_group (sigc::bind (sigc::mem_fun (*this, &RouteGroupMenu::add_item), curr, &group));
+	if (_session) {
+		_session->foreach_route_group (sigc::bind (sigc::mem_fun (*this, &RouteGroupMenu::add_item), curr, &group));
+	}
 }
 
 void
@@ -76,13 +78,17 @@ RouteGroupMenu::set_group (RouteGroup* g)
 void
 RouteGroupMenu::new_group ()
 {
-	RouteGroup* g = new RouteGroup (_session, "", RouteGroup::Active, _default_properties);
+	if (!_session) {
+		return;
+	}
+
+	RouteGroup* g = new RouteGroup (*_session, "", RouteGroup::Active, _default_properties);
 
 	RouteGroupDialog d (g, Gtk::Stock::NEW);
 	int const r = d.do_run ();
 
 	if (r == Gtk::RESPONSE_OK) {
-		_session.add_route_group (g);
+		_session->add_route_group (g);
 		set_group (g);
 	} else {
 		delete g;
diff --git a/gtk2_ardour/route_group_menu.h b/gtk2_ardour/route_group_menu.h
index ba955f64a2..7b9e539ecb 100644
--- a/gtk2_ardour/route_group_menu.h
+++ b/gtk2_ardour/route_group_menu.h
@@ -17,26 +17,28 @@
 
 */
 
+#ifndef __ardour_gtk_route_group_menu_h__
+#define __ardour_gtk_route_group_menu_h__
+
 #include "ardour/route_group.h"
+#include "ardour/session_handle.h"
 
-namespace ARDOUR {
-	class Session;
-}
 
-class RouteGroupMenu : public Gtk::Menu
+class RouteGroupMenu : public Gtk::Menu, public ARDOUR::SessionHandlePtr
 {
 public:
-	RouteGroupMenu (ARDOUR::Session &, ARDOUR::RouteGroup::Property);
+	RouteGroupMenu (ARDOUR::Session*, ARDOUR::RouteGroup::Property);
 
 	void rebuild (ARDOUR::RouteGroup *);
 
 	sigc::signal<void, ARDOUR::RouteGroup*> GroupSelected;
 
-private:
+  private:
 	void add_item (ARDOUR::RouteGroup *, ARDOUR::RouteGroup *, Gtk::RadioMenuItem::Group*);
 	void new_group ();
 	void set_group (ARDOUR::RouteGroup *);
 
-	ARDOUR::Session& _session;
 	ARDOUR::RouteGroup::Property _default_properties;
 };
+
+#endif /* __ardour_gtk_route_group_menu_h__ */
diff --git a/gtk2_ardour/route_params_ui.cc b/gtk2_ardour/route_params_ui.cc
index c9bba4b63b..c948d388d8 100644
--- a/gtk2_ardour/route_params_ui.cc
+++ b/gtk2_ardour/route_params_ui.cc
@@ -181,16 +181,22 @@ RouteParams_UI::add_routes (RouteList& routes)
 
 		//route_select_list.rows().back().select ();
 
-		route->NameChanged.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::route_name_changed), route));
-		route->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::route_removed), route));
+		scoped_connect (route->NameChanged, boost::bind (&RouteParams_UI::route_name_changed, this, boost::weak_ptr<Route>(route)));
+		scoped_connect (route->GoingAway, boost::bind (&RouteParams_UI::route_removed, this, boost::weak_ptr<Route>(route)));
 	}
 }
 
 
 void
-RouteParams_UI::route_name_changed (boost::shared_ptr<Route> route)
+RouteParams_UI::route_name_changed (boost::weak_ptr<Route> wr)
 {
-	ENSURE_GUI_THREAD (*this, &RouteParams_UI::route_name_changed, route)
+	boost::shared_ptr<Route> route (wr.lock());
+
+	if (!route) { 
+		return;
+	}
+
+	ENSURE_GUI_THREAD (*this, &RouteParams_UI::route_name_changed, wr)
 
 	bool found = false ;
 	TreeModel::Children rows = route_display_model->children();
@@ -216,14 +222,13 @@ RouteParams_UI::route_name_changed (boost::shared_ptr<Route> route)
 void
 RouteParams_UI::setup_processor_boxes()
 {
-	if (session && _route) {
+	if (_session && _route) {
 
 		// just in case... shouldn't need this
 		cleanup_processor_boxes();
 
 		// construct new redirect boxes
-		insert_box = new ProcessorBox(*session,
-				sigc::mem_fun(*this, &RouteParams_UI::plugin_selector), _rr_selection, 0);
+		insert_box = new ProcessorBox (_session, boost::bind (&RouteParams_UI::plugin_selector, this), _rr_selection, 0);
 		insert_box->set_route (_route);
 
 		redir_hpane.pack1 (*insert_box);
@@ -265,18 +270,19 @@ RouteParams_UI::cleanup_latency_frame ()
 		latency_packer.remove (*latency_widget);
 		latency_packer.remove (latency_button_box);
 		latency_packer.remove (delay_label);
+		latency_connections.drop_connections ();
+		latency_click_connection.disconnect ();
+
 		delete latency_widget;
 		latency_widget = 0;
-		latency_conn.disconnect ();
-		delay_conn.disconnect ();
-		latency_apply_conn.disconnect ();
+		
 	}
 }
 
 void
 RouteParams_UI::setup_latency_frame ()
 {
-	latency_widget = new LatencyGUI (*(_route->output()), session->frame_rate(), session->engine().frames_per_cycle());
+	latency_widget = new LatencyGUI (*(_route->output()), _session->frame_rate(), _session->engine().frames_per_cycle());
 
 	char buf[128];
 	snprintf (buf, sizeof (buf), _("Playback delay: %u samples"), _route->initial_delay());
@@ -286,9 +292,9 @@ RouteParams_UI::setup_latency_frame ()
 	latency_packer.pack_start (latency_button_box, false, false);
 	latency_packer.pack_start (delay_label);
 
-	latency_apply_conn = latency_apply_button.signal_clicked().connect (sigc::mem_fun (*latency_widget, &LatencyGUI::finish));
-	latency_conn = _route->signal_latency_changed.connect (sigc::mem_fun (*this, &RouteParams_UI::refresh_latency));
-	delay_conn = _route->initial_delay_changed.connect (sigc::mem_fun (*this, &RouteParams_UI::refresh_latency));
+	latency_click_connection = latency_apply_button.signal_clicked().connect (sigc::mem_fun (*latency_widget, &LatencyGUI::finish));
+	latency_connections.add_connection (_route->signal_latency_changed.connect (sigc::mem_fun (*this, &RouteParams_UI::refresh_latency)));
+	latency_connections.add_connection ( _route->initial_delay_changed.connect (sigc::mem_fun (*this, &RouteParams_UI::refresh_latency)));
 
 	latency_frame.add (latency_packer);
 	latency_frame.show_all ();
@@ -300,13 +306,13 @@ RouteParams_UI::setup_io_frames()
 	cleanup_io_frames();
 
 	// input
-	_input_iosel = new IOSelector (this, session, _route->input());
+	_input_iosel = new IOSelector (this, _session, _route->input());
 	_input_iosel->setup ();
 	input_frame.add (*_input_iosel);
 	input_frame.show_all();
 
 	// output
-	_output_iosel = new IOSelector (this, session, _route->output());
+	_output_iosel = new IOSelector (this, _session, _route->output());
 	_output_iosel->setup ();
 	output_frame.add (*_output_iosel);
 	output_frame.show_all();
@@ -341,7 +347,7 @@ RouteParams_UI::cleanup_view (bool stopupdate)
 			  plugui->stop_updating (0);
 		}
 
-		_plugin_conn.disconnect();
+		_processor_going_away_connection.disconnect ();
  		redir_hpane.remove(*_active_view);
 		delete _active_view;
 		_active_view = 0;
@@ -349,9 +355,15 @@ RouteParams_UI::cleanup_view (bool stopupdate)
 }
 
 void
-RouteParams_UI::route_removed (boost::shared_ptr<Route> route)
+RouteParams_UI::route_removed (boost::weak_ptr<Route> wr)
 {
-	ENSURE_GUI_THREAD (*this, &RouteParams_UI::route_removed, route)
+	boost::shared_ptr<Route> route (wr.lock());
+
+	if (!route) { 
+		return;
+	}
+
+	ENSURE_GUI_THREAD (*this, &RouteParams_UI::route_removed, wr)
 
 	TreeModel::Children rows = route_display_model->children();
 	TreeModel::Children::iterator ri;
@@ -380,29 +392,27 @@ void
 RouteParams_UI::set_session (Session *sess)
 {
 	ArdourDialog::set_session (sess);
-
+	
 	route_display_model->clear();
+	_plugin_selector->set_session (_session);
 
-	if (session) {
-		boost::shared_ptr<RouteList> r = session->get_routes();
+	if (_session) {
+		boost::shared_ptr<RouteList> r = _session->get_routes();
 		add_routes (*r);
-		session->GoingAway.connect (sigc::mem_fun(*this, &ArdourDialog::session_gone));
-		session->RouteAdded.connect (sigc::mem_fun(*this, &RouteParams_UI::add_routes));
+		_session_connections.add_connection (_session->RouteAdded.connect (sigc::mem_fun(*this, &RouteParams_UI::add_routes)));
 		start_updating ();
 	} else {
 		stop_updating ();
 	}
-
-	//route_select_list.thaw ();
-
-	_plugin_selector->set_session (session);
 }
 
 
 void
-RouteParams_UI::session_gone ()
+RouteParams_UI::session_going_away ()
 {
-	ENSURE_GUI_THREAD (*this, &RouteParams_UI::session_gone)
+	ENSURE_GUI_THREAD (*this, &RouteParams_UI::session_going_away);
+
+	SessionHandlePtr::session_going_away ();
 
 	route_display_model->clear();
 
@@ -414,9 +424,6 @@ RouteParams_UI::session_gone ()
 	_route.reset ((Route*) 0);
 	_processor.reset ((Processor*) 0);
 	update_title();
-
-	ArdourDialog::session_gone();
-
 }
 
 void
@@ -436,8 +443,7 @@ RouteParams_UI::route_selected()
 
 		// remove event binding from previously selected
 		if (_route) {
-			_route_conn.disconnect();
-			_route_ds_conn.disconnect();
+			_route_processors_connection.disconnect ();
 			cleanup_processor_boxes();
 			cleanup_view();
 			cleanup_io_frames();
@@ -452,9 +458,8 @@ RouteParams_UI::route_selected()
 		setup_processor_boxes();
 		setup_latency_frame ();
 
-		// sigc::bind to redirects changed event for this route
-		_route_conn = route->processors_changed.connect (sigc::mem_fun(*this, &RouteParams_UI::processors_changed));
-
+		_route_processors_connection = route->processors_changed.connect (boost::bind (&RouteParams_UI::processors_changed, this, _1));
+		
 		track_input_label.set_text (_route->name());
 
 		update_title();
@@ -462,7 +467,7 @@ RouteParams_UI::route_selected()
 	} else {
 		// no selection
 		if (_route) {
-			_route_conn.disconnect();
+			_route_processors_connection.disconnect ();
 
 			// remove from view
 			cleanup_io_frames();
@@ -505,64 +510,62 @@ RouteParams_UI::show_track_menu()
 }
 
 void
-RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> insert)
+RouteParams_UI::redirect_selected (boost::shared_ptr<ARDOUR::Processor> proc)
 {
 	boost::shared_ptr<Send> send;
 	boost::shared_ptr<Return> retrn;
 	boost::shared_ptr<PluginInsert> plugin_insert;
 	boost::shared_ptr<PortInsert> port_insert;
 
-	if ((send = boost::dynamic_pointer_cast<Send> (insert)) != 0) {
+	if ((send = boost::dynamic_pointer_cast<Send> (proc)) != 0) {
 
-		SendUI *send_ui = new SendUI (this, send, *session);
+		SendUI *send_ui = new SendUI (this, send, _session);
 
 		cleanup_view();
-		_plugin_conn = send->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::redirect_going_away),
-							      insert));
+		_processor_going_away_connection = send->GoingAway.connect (boost::bind (&RouteParams_UI::processor_going_away, this, 
+											 boost::weak_ptr<Processor>(proc)));
+
 		_active_view = send_ui;
 
 		redir_hpane.add2 (*_active_view);
 		redir_hpane.show_all();
 
-	} else if ((retrn = boost::dynamic_pointer_cast<Return> (insert)) != 0) {
+	} else if ((retrn = boost::dynamic_pointer_cast<Return> (proc)) != 0) {
 
-		ReturnUI *return_ui = new ReturnUI (this, retrn, *session);
+		ReturnUI *return_ui = new ReturnUI (this, retrn, _session);
 
 		cleanup_view();
-		_plugin_conn = retrn->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::redirect_going_away),
-							       insert));
+		_processor_going_away_connection = retrn->GoingAway.connect (boost::bind (&RouteParams_UI::processor_going_away, this,
+											  boost::weak_ptr<Processor>(proc)));
 		_active_view = return_ui;
 
 		redir_hpane.add2 (*_active_view);
 		redir_hpane.show_all();
 
-	} else if ((plugin_insert = boost::dynamic_pointer_cast<PluginInsert> (insert)) != 0) {
+	} else if ((plugin_insert = boost::dynamic_pointer_cast<PluginInsert> (proc)) != 0) {
 
 		GenericPluginUI *plugin_ui = new GenericPluginUI (plugin_insert, true);
 
 		cleanup_view();
-		_plugin_conn = plugin_insert->plugin()->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::plugin_going_away),
-										 PreFader));
+		_processor_going_away_connection = plugin_insert->plugin()->GoingAway.connect (boost::bind (&RouteParams_UI::plugin_going_away, this, PreFader));
 		plugin_ui->start_updating (0);
 		_active_view = plugin_ui;
 		redir_hpane.pack2 (*_active_view);
 		redir_hpane.show_all();
 
-	} else if ((port_insert = boost::dynamic_pointer_cast<PortInsert> (insert)) != 0) {
+	} else if ((port_insert = boost::dynamic_pointer_cast<PortInsert> (proc)) != 0) {
 
-		PortInsertUI *portinsert_ui = new PortInsertUI (this, session, port_insert);
+		PortInsertUI *portinsert_ui = new PortInsertUI (this, _session, port_insert);
 
 		cleanup_view();
-		_plugin_conn = port_insert->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, &RouteParams_UI::redirect_going_away),
-								     insert));
+		_processor_going_away_connection = port_insert->GoingAway.connect (boost::bind (&RouteParams_UI::processor_going_away, this, boost::weak_ptr<Processor> (proc)));
 		_active_view = portinsert_ui;
 		redir_hpane.pack2 (*_active_view);
 		portinsert_ui->redisplay();
 		redir_hpane.show_all();
 	}
 
-	_processor = insert;
-
+	_processor = proc;
 	update_title();
 
 }
@@ -581,14 +584,19 @@ RouteParams_UI::plugin_going_away (Placement place)
 }
 
 void
-RouteParams_UI::redirect_going_away (boost::shared_ptr<ARDOUR::Processor> insert)
-
+RouteParams_UI::processor_going_away (boost::weak_ptr<ARDOUR::Processor> wproc)
 {
-	ENSURE_GUI_THREAD (*this, &RouteParams_UI::redirect_going_away, insert)
+	boost::shared_ptr<Processor> proc = (wproc.lock());
+
+	if (!proc) {
+		return;
+	}
+
+	ENSURE_GUI_THREAD (*this, &RouteParams_UI::processor_going_away, wproc)
 
 	printf ("redirect going away\n");
 	// delete the current view without calling finish
-	if (insert == _processor) {
+	if (proc == _processor) {
 		cleanup_view (false);
 		_processor.reset ((Processor*) 0);
 	}
diff --git a/gtk2_ardour/route_params_ui.h b/gtk2_ardour/route_params_ui.h
index 4d21805778..2dcb1b921d 100644
--- a/gtk2_ardour/route_params_ui.h
+++ b/gtk2_ardour/route_params_ui.h
@@ -33,6 +33,7 @@
 #include <gtkmm/treeview.h>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/ardour.h"
 
@@ -54,14 +55,14 @@ namespace ARDOUR {
 
 class PluginSelector;
 
-class RouteParams_UI : public ArdourDialog
+class RouteParams_UI : public ArdourDialog, public PBD::ScopedConnectionList
 {
   public:
 	RouteParams_UI ();
 	~RouteParams_UI();
 
-	void set_session (ARDOUR::Session *);
-	void session_gone ();
+	void set_session (ARDOUR::Session*);
+	void session_going_away ();
 	PluginSelector*  plugin_selector() { return _plugin_selector; }
 
   private:
@@ -105,9 +106,9 @@ class RouteParams_UI : public ArdourDialog
 	Gtk::Button              latency_apply_button;
 	LatencyGUI*              latency_widget;
 	Gtk::Label               delay_label;
-	sigc::connection         latency_conn;
-	sigc::connection         delay_conn;
-	sigc::connection         latency_apply_conn;
+
+	PBD::ScopedConnectionList latency_connections;
+	sigc::connection          latency_click_connection;
 
 	void refresh_latency ();
 
@@ -125,11 +126,10 @@ class RouteParams_UI : public ArdourDialog
 	RouteRedirectSelection  _rr_selection;
 
 	boost::shared_ptr<ARDOUR::Route> _route;
-	sigc::connection            _route_conn;
-	sigc::connection            _route_ds_conn;
+	boost::signals2::scoped_connection _route_processors_connection;
 
 	boost::shared_ptr<ARDOUR::Processor> _processor;
-	sigc::connection                    _plugin_conn;
+	boost::signals2::scoped_connection _processor_going_away_connection;
 
 
 	enum ConfigView {
@@ -161,8 +161,8 @@ class RouteParams_UI : public ArdourDialog
 
 	void add_routes (ARDOUR::RouteList&);
 
-	void route_name_changed (boost::shared_ptr<ARDOUR::Route> route);
-	void route_removed (boost::shared_ptr<ARDOUR::Route> route);
+	void route_name_changed (boost::weak_ptr<ARDOUR::Route> route);
+	void route_removed (boost::weak_ptr<ARDOUR::Route> route);
 
 
 	void route_selected();
@@ -182,7 +182,7 @@ class RouteParams_UI : public ArdourDialog
 	void redirect_selected (boost::shared_ptr<ARDOUR::Processor>);
 
 	void plugin_going_away (ARDOUR::Placement);
-	void redirect_going_away (boost::shared_ptr<ARDOUR::Processor>);
+	void processor_going_away (boost::weak_ptr<ARDOUR::Processor>);
 
 	gint edit_input_configuration (GdkEventButton *ev);
 	gint edit_output_configuration (GdkEventButton *ev);
diff --git a/gtk2_ardour/route_processor_selection.cc b/gtk2_ardour/route_processor_selection.cc
index 1af1e0c968..102cd724dd 100644
--- a/gtk2_ardour/route_processor_selection.cc
+++ b/gtk2_ardour/route_processor_selection.cc
@@ -26,6 +26,7 @@
 #include "ardour/route.h"
 
 #include "route_processor_selection.h"
+#include "gui_thread.h"
 
 #include "i18n.h"
 
@@ -92,18 +93,28 @@ RouteRedirectSelection::add (boost::shared_ptr<Route> r)
 {
 	if (find (routes.begin(), routes.end(), r) == routes.end()) {
 		routes.push_back (r);
+		r->GoingAway.connect (boost::bind (&RouteRedirectSelection::removed, this, boost::weak_ptr<Route>(r)));
+		RoutesChanged();
+	}
+}
 
-		// XXX SHAREDPTR FIXME
-		// void (RouteRedirectSelection::*pmf)(Route*) = &RouteRedirectSelection::remove;
-		// r->GoingAway.connect (sigc::bind (sigc::mem_fun(*this, pmf), r));
+void
+RouteRedirectSelection::removed (boost::weak_ptr<Route> wr)
+{
+	boost::shared_ptr<Route> r (wr.lock());
 
-		RoutesChanged();
+	if (!r) {
+		return;
 	}
+
+	remove (r);
 }
 
 void
 RouteRedirectSelection::remove (boost::shared_ptr<Route> r)
 {
+	ENSURE_GUI_THREAD (*this, &RouteRedirectSelection::remove, r);
+
 	list<boost::shared_ptr<Route> >::iterator i;
 	if ((i = find (routes.begin(), routes.end(), r)) != routes.end()) {
 		routes.erase (i);
diff --git a/gtk2_ardour/route_processor_selection.h b/gtk2_ardour/route_processor_selection.h
index 83bdbc2d8b..eb76d481dd 100644
--- a/gtk2_ardour/route_processor_selection.h
+++ b/gtk2_ardour/route_processor_selection.h
@@ -21,12 +21,12 @@
 #define __ardour_gtk_route_processor_selection_h__
 
 #include <vector>
-#include <sigc++/signal.h>
+#include "pbd/scoped_connections.h"
 
 #include "processor_selection.h"
 #include "route_selection.h"
 
-class RouteRedirectSelection : public sigc::trackable
+class RouteRedirectSelection : public PBD::ScopedConnectionList, public sigc::trackable
 {
   public:
 	ProcessorSelection processors;
@@ -53,6 +53,10 @@ class RouteRedirectSelection : public sigc::trackable
 	void clear_routes ();
 
 	bool selected (boost::shared_ptr<ARDOUR::Route>);
+
+  private:
+	void removed (boost::weak_ptr<ARDOUR::Route>);
+
 };
 
 bool operator==(const RouteRedirectSelection& a, const RouteRedirectSelection& b);
diff --git a/gtk2_ardour/route_time_axis.cc b/gtk2_ardour/route_time_axis.cc
index 1f75bec50d..e652fbc4a3 100644
--- a/gtk2_ardour/route_time_axis.cc
+++ b/gtk2_ardour/route_time_axis.cc
@@ -100,7 +100,7 @@ RouteTimeAxisView::setup_slider_pix ()
 	}
 }
 
-RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session& sess, boost::shared_ptr<Route> rt, Canvas& canvas)
+RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session* sess, boost::shared_ptr<Route> rt, Canvas& canvas)
 	: AxisView(sess)
 	, RouteUI(rt, sess)
 	, TimeAxisView(sess,ed,(TimeAxisView*) 0, canvas)
@@ -189,7 +189,7 @@ RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session& sess, boost::sh
 		controls_table.attach (*rec_enable_button, 5, 6, 0, 1, Gtk::FILL|Gtk::EXPAND, Gtk::FILL|Gtk::EXPAND, 0, 0);
 		ARDOUR_UI::instance()->tooltips().set_tip(*rec_enable_button, _("Record"));
 
-		rec_enable_button->set_sensitive (_session.writable());
+		rec_enable_button->set_sensitive (_session->writable());
 	}
 
 	controls_hbox.pack_start(gm.get_level_meter(), false, false);
@@ -269,7 +269,7 @@ RouteTimeAxisView::RouteTimeAxisView (PublicEditor& ed, Session& sess, boost::sh
 
 RouteTimeAxisView::~RouteTimeAxisView ()
 {
-	GoingAway (); /* EMIT_SIGNAL */
+	drop_references ();
 
 	for (list<ProcessorAutomationInfo*>::iterator i = processor_automation.begin(); i != processor_automation.end(); ++i) {
 		delete *i;
@@ -1044,8 +1044,8 @@ RouteTimeAxisView::use_copy_playlist (bool prompt, vector<boost::shared_ptr<Play
 		name = resolve_new_group_playlist_name(name, playlists_before_op);
 	}
 
-	while (_session.playlists->by_name(name)) {
-		name = Playlist::bump_name (name, _session);
+	while (_session->playlists->by_name(name)) {
+		name = Playlist::bump_name (name, *_session);
 	}
 
 	// TODO: The prompter "new" button should be de-activated if the user
@@ -1096,8 +1096,8 @@ RouteTimeAxisView::use_new_playlist (bool prompt, vector<boost::shared_ptr<Playl
 		name = resolve_new_group_playlist_name(name,playlists_before_op);
 	}
 
-	while (_session.playlists->by_name(name)) {
-		name = Playlist::bump_name (name, _session);
+	while (_session->playlists->by_name(name)) {
+		name = Playlist::bump_name (name, *_session);
 	}
 
 
@@ -1325,10 +1325,10 @@ RouteTimeAxisView::name_entry_changed ()
 		return;
 	}
 
-	if (!_session.route_name_unique (x)) {
+	if (!_session->route_name_unique (x)) {
 		ARDOUR_UI::instance()->popup_error (_("A track already exists with that name"));
 		name_entry.set_text (_route->name());
-	} else if (_session.route_name_internal (x)) {
+	} else if (_session->route_name_internal (x)) {
 		ARDOUR_UI::instance()->popup_error (_("You cannot create a track with that name as it is reserved for Ardour"));
 		name_entry.set_text (_route->name());
 	} else {
@@ -1408,7 +1408,7 @@ RouteTimeAxisView::cut_copy_clear (Selection& selection, CutCopyOp op)
 	case Cut:
 		if ((what_we_got = playlist->cut (time)) != 0) {
 			_editor.get_cut_buffer().add (what_we_got);
-			_session.add_command( new MementoCommand<Playlist>(*playlist.get(), &before, &playlist->get_state()));
+			_session->add_command( new MementoCommand<Playlist>(*playlist.get(), &before, &playlist->get_state()));
 			ret = true;
 		}
 		break;
@@ -1420,7 +1420,7 @@ RouteTimeAxisView::cut_copy_clear (Selection& selection, CutCopyOp op)
 
 	case Clear:
 		if ((what_we_got = playlist->cut (time)) != 0) {
-			_session.add_command( new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+			_session->add_command( new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 			what_we_got->release ();
 			ret = true;
 		}
@@ -1452,7 +1452,7 @@ RouteTimeAxisView::paste (nframes_t pos, float times, Selection& selection, size
 
 	XMLNode &before = playlist->get_state();
 	playlist->paste (*p, pos, times);
-	_session.add_command( new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
+	_session->add_command( new MementoCommand<Playlist>(*playlist, &before, &playlist->get_state()));
 
 	return true;
 }
@@ -1494,7 +1494,7 @@ RouteTimeAxisView::build_playlist_menu (Gtk::Menu * menu)
 	boost::shared_ptr<Diskstream> ds = get_diskstream();
 	RadioMenuItem::Group playlist_group;
 
-	_session.playlists->get (playlists);
+	_session->playlists->get (playlists);
 
 	for (vector<boost::shared_ptr<Playlist> >::iterator i = playlists.begin(); i != playlists.end(); ++i) {
 
@@ -1584,7 +1584,7 @@ RouteTimeAxisView::use_playlist (boost::weak_ptr<Playlist> wpl)
 					continue;
 				}
 
-				boost::shared_ptr<Playlist> ipl = session().playlists->by_name(playlist_name);
+				boost::shared_ptr<Playlist> ipl = session()->playlists->by_name(playlist_name);
 				if (!ipl) {
 					// No playlist for this track for this take yet, make it
 					track->diskstream()->use_new_playlist();
diff --git a/gtk2_ardour/route_time_axis.h b/gtk2_ardour/route_time_axis.h
index f37f32b1fa..c210a55cf3 100644
--- a/gtk2_ardour/route_time_axis.h
+++ b/gtk2_ardour/route_time_axis.h
@@ -71,7 +71,7 @@ class RouteGroupMenu;
 class RouteTimeAxisView : public RouteUI, public TimeAxisView
 {
 public:
- 	RouteTimeAxisView (PublicEditor&, ARDOUR::Session&, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
+ 	RouteTimeAxisView (PublicEditor&, ARDOUR::Session*, boost::shared_ptr<ARDOUR::Route>, ArdourCanvas::Canvas& canvas);
  	virtual ~RouteTimeAxisView ();
 
 	void show_selection (TimeSelection&);
diff --git a/gtk2_ardour/route_ui.cc b/gtk2_ardour/route_ui.cc
index 2b5c892c0c..31841c97ba 100644
--- a/gtk2_ardour/route_ui.cc
+++ b/gtk2_ardour/route_ui.cc
@@ -29,7 +29,6 @@
 #include "ardour/dB.h"
 #include "pbd/memento_command.h"
 #include "pbd/stacktrace.h"
-#include "pbd/shiva.h"
 #include "pbd/controllable.h"
 #include "pbd/enumwriter.h"
 
@@ -65,13 +64,13 @@ using namespace Gtkmm2ext;
 using namespace ARDOUR;
 using namespace PBD;
 
-RouteUI::RouteUI (ARDOUR::Session& sess)
+RouteUI::RouteUI (ARDOUR::Session* sess)
 	: AxisView(sess)
 {
 	init ();
 }
 
-RouteUI::RouteUI (boost::shared_ptr<ARDOUR::Route> rt, ARDOUR::Session& sess)
+RouteUI::RouteUI (boost::shared_ptr<ARDOUR::Route> rt, ARDOUR::Session* sess)
 	: AxisView(sess)
 {
 	init ();
@@ -137,8 +136,8 @@ RouteUI::init ()
 	show_sends_button->set_self_managed (true);
 	UI::instance()->set_tip (show_sends_button, _("make mixer strips show sends to this bus"), "");
 
-	_session.SoloChanged.connect (sigc::mem_fun(*this, &RouteUI::solo_changed_so_update_mute));
-	_session.TransportStateChange.connect (sigc::mem_fun (*this, &RouteUI::check_rec_enable_sensitivity));
+	_session_connections.add_connection (_session->SoloChanged.connect (sigc::mem_fun(*this, &RouteUI::solo_changed_so_update_mute)));
+	_session_connections.add_connection (_session->TransportStateChange.connect (sigc::mem_fun (*this, &RouteUI::check_rec_enable_sensitivity)));
 
 	Config->ParameterChanged.connect (sigc::mem_fun (*this, &RouteUI::parameter_changed));
 }
@@ -146,12 +145,8 @@ RouteUI::init ()
 void
 RouteUI::reset ()
 {
-	//Remove route connections associated with us.
-	for (vector<sigc::connection>::iterator it = connections.begin(); it!=connections.end(); ++it) {
-	    (*it).disconnect();
-	}
-
-	connections.clear ();
+	route_going_away_connection.disconnect();
+	connections.drop_connections ();
 
 	delete solo_menu;
 	solo_menu = 0;
@@ -170,6 +165,14 @@ RouteUI::reset ()
 }
 
 void
+RouteUI::self_delete ()
+{
+	route_going_away_connection.disconnect ();
+	connections.drop_connections ();
+	delete_when_idle (this);
+}
+
+void
 RouteUI::set_route (boost::shared_ptr<Route> rp)
 {
 	reset ();
@@ -180,28 +183,24 @@ RouteUI::set_route (boost::shared_ptr<Route> rp)
 		set_color (unique_random_color());
 	}
 
-	/* no, there is no memory leak here. This object cleans itself (and other stuff)
-	   up when the route is destroyed.
-	*/
-
 	if (self_destruct) {
-		new PairedShiva<Route,RouteUI> (*_route, *this);
+		route_going_away_connection = rp->GoingAway.connect (boost::bind (&RouteUI::self_delete, this));
 	}
 
 	mute_button->set_controllable (_route->mute_control());
 	solo_button->set_controllable (_route->solo_control());
 
-	connections.push_back (_route->active_changed.connect (sigc::mem_fun (*this, &RouteUI::route_active_changed)));
-	connections.push_back (_route->mute_changed.connect (sigc::mem_fun(*this, &RouteUI::mute_changed)));
-	connections.push_back (_route->solo_changed.connect (sigc::mem_fun(*this, &RouteUI::solo_changed)));
-	connections.push_back (_route->listen_changed.connect (sigc::mem_fun(*this, &RouteUI::listen_changed)));
-	connections.push_back (_route->solo_isolated_changed.connect (sigc::mem_fun(*this, &RouteUI::solo_changed)));
+	connections.add_connection (_route->active_changed.connect (sigc::mem_fun (*this, &RouteUI::route_active_changed)));
+	connections.add_connection (_route->mute_changed.connect (sigc::mem_fun(*this, &RouteUI::mute_changed)));
+	connections.add_connection (_route->solo_changed.connect (sigc::mem_fun(*this, &RouteUI::solo_changed)));
+	connections.add_connection (_route->listen_changed.connect (sigc::mem_fun(*this, &RouteUI::listen_changed)));
+	connections.add_connection (_route->solo_isolated_changed.connect (sigc::mem_fun(*this, &RouteUI::solo_changed)));
 
-	if (_session.writable() && is_track()) {
+	if (_session->writable() && is_track()) {
 		boost::shared_ptr<Track> t = boost::dynamic_pointer_cast<Track>(_route);
 
-		connections.push_back (t->diskstream()->RecordEnableChanged.connect (sigc::mem_fun (*this, &RouteUI::route_rec_enable_changed)));
-		connections.push_back (_session.RecordStateChanged.connect (sigc::mem_fun (*this, &RouteUI::session_rec_enable_changed)));
+		connections.add_connection (t->diskstream()->RecordEnableChanged.connect (sigc::mem_fun (*this, &RouteUI::route_rec_enable_changed)));
+		connections.add_connection (_session->RecordStateChanged.connect (sigc::mem_fun (*this, &RouteUI::session_rec_enable_changed)));
 
 		rec_enable_button->show();
  		rec_enable_button->set_controllable (t->rec_enable_control());
@@ -265,10 +264,10 @@ RouteUI::mute_press (GdkEventButton* ev)
 				if (Keyboard::modifier_state_equals (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::TertiaryModifier))) {
 
 					if (_mute_release) {
-						_mute_release->routes = _session.get_routes ();
+						_mute_release->routes = _session->get_routes ();
 					}
 
-					_session.set_mute (_session.get_routes(), !_route->muted());
+					_session->set_mute (_session->get_routes(), !_route->muted());
 
 				} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
 
@@ -278,10 +277,10 @@ RouteUI::mute_press (GdkEventButton* ev)
 
 					if (ev->button == 1 && _route->route_group()) {
 						if (_mute_release) {
-							_mute_release->routes = _session.get_routes ();
+							_mute_release->routes = _session->get_routes ();
 						}
 								
-						_session.set_mute (_session.get_routes(), !_route->muted(), Session::rt_cleanup, true);
+						_session->set_mute (_session->get_routes(), !_route->muted(), Session::rt_cleanup, true);
 					}
 
 				} else {
@@ -295,7 +294,7 @@ RouteUI::mute_press (GdkEventButton* ev)
 						_mute_release->routes = rl;
 					}
 
-					_session.set_mute (rl, !_route->muted());
+					_session->set_mute (rl, !_route->muted());
 
 				}
 			}
@@ -311,7 +310,7 @@ RouteUI::mute_release (GdkEventButton*)
 {
 	if (!ignore_toggle) {
 		if (_mute_release){
-			_session.set_mute (_mute_release->routes, _mute_release->active, Session::rt_cleanup, true);
+			_session->set_mute (_mute_release->routes, _mute_release->active, Session::rt_cleanup, true);
 			delete _mute_release;
 			_mute_release = 0;
 		}
@@ -362,13 +361,13 @@ RouteUI::solo_press(GdkEventButton* ev)
 					/* Primary-Tertiary-click applies change to all routes */
 
 					if (_solo_release) {
-						_solo_release->routes = _session.get_routes ();
+						_solo_release->routes = _session->get_routes ();
 					}
 					
 					if (Config->get_solo_control_is_listen_control()) {
-						_session.set_listen (_session.get_routes(), !_route->listening(),  Session::rt_cleanup, true);
+						_session->set_listen (_session->get_routes(), !_route->listening(),  Session::rt_cleanup, true);
 					} else {
-						_session.set_solo (_session.get_routes(), !_route->soloed(),  Session::rt_cleanup, true);
+						_session->set_solo (_session->get_routes(), !_route->soloed(),  Session::rt_cleanup, true);
 					}
 					
 				} else if (Keyboard::modifier_state_contains (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::SecondaryModifier))) {
@@ -378,7 +377,7 @@ RouteUI::solo_press(GdkEventButton* ev)
 					if (_solo_release) {
 						_solo_release->exclusive = true;
 
-						boost::shared_ptr<RouteList> routes = _session.get_routes();
+						boost::shared_ptr<RouteList> routes = _session->get_routes();
 
 						for (RouteList::iterator i = routes->begin(); i != routes->end(); ++i) {
 							if ((*i)->soloed ()) {
@@ -392,7 +391,7 @@ RouteUI::solo_press(GdkEventButton* ev)
 					if (Config->get_solo_control_is_listen_control()) {
 						/* ??? we need a just_one_listen() method */
 					} else {
-						_session.set_just_one_solo (_route, true);
+						_session->set_just_one_solo (_route, true);
 					}
 
 				} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::TertiaryModifier)) {
@@ -416,9 +415,9 @@ RouteUI::solo_press(GdkEventButton* ev)
 						}
 					
 						if (Config->get_solo_control_is_listen_control()) {
-							_session.set_listen (_route->route_group()->route_list(), !_route->listening(),  Session::rt_cleanup, true);
+							_session->set_listen (_route->route_group()->route_list(), !_route->listening(),  Session::rt_cleanup, true);
 						} else {
-							_session.set_solo (_route->route_group()->route_list(), !_route->soloed(),  Session::rt_cleanup, true);
+							_session->set_solo (_route->route_group()->route_list(), !_route->soloed(),  Session::rt_cleanup, true);
 						}
 					}
 					
@@ -434,9 +433,9 @@ RouteUI::solo_press(GdkEventButton* ev)
 					}
 
 					if (Config->get_solo_control_is_listen_control()) {
-						_session.set_listen (rl, !_route->listening());
+						_session->set_listen (rl, !_route->listening());
 					} else {
-						_session.set_solo (rl, !_route->soloed());
+						_session->set_solo (rl, !_route->soloed());
 					}
 				}
 			}
@@ -456,7 +455,7 @@ RouteUI::solo_release (GdkEventButton*)
 			if (_solo_release->exclusive) {
 
 			} else {
-				_session.set_solo (_solo_release->routes, _solo_release->active, Session::rt_cleanup, true);
+				_session->set_solo (_solo_release->routes, _solo_release->active, Session::rt_cleanup, true);
 			}
 
 			delete _solo_release;
@@ -474,7 +473,7 @@ RouteUI::rec_enable_press(GdkEventButton* ev)
 		return true;
 	}
 
-	if (!_session.engine().connected()) {
+	if (!_session->engine().connected()) {
 	        MessageDialog msg (_("Not connected to JACK - cannot engage record"));
 		msg.run ();
 		return true;
@@ -489,7 +488,7 @@ RouteUI::rec_enable_press(GdkEventButton* ev)
 
 		} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::ModifierMask (Keyboard::PrimaryModifier|Keyboard::TertiaryModifier))) {
 
-			_session.set_record_enable (_session.get_routes(), !rec_enable_button->get_active());
+			_session->set_record_enable (_session->get_routes(), !rec_enable_button->get_active());
 
 		} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
 
@@ -497,7 +496,7 @@ RouteUI::rec_enable_press(GdkEventButton* ev)
 			   NOTE: Primary-button2 is MIDI learn.
 			*/
 			if (ev->button == 1 && _route->route_group()) {
-				_session.set_record_enable (_route->route_group()->route_list(), !rec_enable_button->get_active(), Session::rt_cleanup, true);
+				_session->set_record_enable (_route->route_group()->route_list(), !rec_enable_button->get_active(), Session::rt_cleanup, true);
 			}
 
 		} else if (Keyboard::is_context_menu_event (ev)) {
@@ -508,7 +507,7 @@ RouteUI::rec_enable_press(GdkEventButton* ev)
 
 			boost::shared_ptr<RouteList> rl (new RouteList);
 			rl->push_back (route());
-			_session.set_record_enable (rl, !rec_enable_button->get_active());
+			_session->set_record_enable (rl, !rec_enable_button->get_active());
 		}
 	}
 
@@ -543,7 +542,7 @@ RouteUI::build_sends_menu ()
 void
 RouteUI::create_sends (Placement p)
 {
-	_session.globally_add_internal_sends (_route, p);
+	_session->globally_add_internal_sends (_route, p);
 }
 
 void
@@ -564,25 +563,25 @@ RouteUI::create_selected_sends (Placement p)
 		}
 	}
 	
-	_session.add_internal_sends (_route, p, rlist);
+	_session->add_internal_sends (_route, p, rlist);
 }
 
 void
 RouteUI::set_sends_gain_from_track ()
 {
-	_session.globally_set_send_gains_from_track (_route);
+	_session->globally_set_send_gains_from_track (_route);
 }
 
 void
 RouteUI::set_sends_gain_to_zero ()
 {
-	_session.globally_set_send_gains_to_zero (_route);
+	_session->globally_set_send_gains_to_zero (_route);
 }
 
 void
 RouteUI::set_sends_gain_to_unity ()
 {
-	_session.globally_set_send_gains_to_unity (_route);
+	_session->globally_set_send_gains_to_unity (_route);
 }
 
 bool
@@ -767,7 +766,7 @@ RouteUI::mute_changed(void* /*src*/)
 }
 
 int
-RouteUI::mute_visual_state (Session& s, boost::shared_ptr<Route> r)
+RouteUI::mute_visual_state (Session* s, boost::shared_ptr<Route> r)
 {
 	if (r->is_master() || r->is_control()) {
 		return 0;
@@ -778,7 +777,7 @@ RouteUI::mute_visual_state (Session& s, boost::shared_ptr<Route> r)
 		if (r->muted ()) {
 			/* full mute */
 			return 2;
-		} else if (s.soloing() && !r->soloed() && !r->solo_isolated()) {
+		} else if (s->soloing() && !r->soloed() && !r->solo_isolated()) {
 			/* mute-because-not-soloed */
 			return 1;
 		} else {
@@ -851,7 +850,7 @@ RouteUI::update_rec_display ()
 
 	if (model) {
 
-		switch (_session.record_status ()) {
+		switch (_session->record_status ()) {
 		case Session::Recording:
 			rec_enable_button->set_visual_state (1);
 			break;
@@ -1110,7 +1109,7 @@ RouteUI::remove_this_route ()
 gint
 RouteUI::idle_remove_this_route (RouteUI *rui)
 {
-	rui->_session.remove_route (rui->_route);
+	rui->_session->remove_route (rui->_route);
 	return false;
 }
 
@@ -1329,7 +1328,7 @@ RouteUI::map_frozen ()
 void
 RouteUI::adjust_latency ()
 {
-	LatencyDialog dialog (_route->name() + _(" latency"), *(_route->output()), _session.frame_rate(), _session.engine().frames_per_cycle());
+	LatencyDialog dialog (_route->name() + _(" latency"), *(_route->output()), _session->frame_rate(), _session->engine().frames_per_cycle());
 }
 
 void
@@ -1370,7 +1369,7 @@ RouteUI::save_as_template ()
 void
 RouteUI::check_rec_enable_sensitivity ()
 {
-	if (_session.transport_rolling() && rec_enable_button->get_active() && Config->get_disable_disarm_during_roll()) {
+	if (_session->transport_rolling() && rec_enable_button->get_active() && Config->get_disable_disarm_during_roll()) {
 		rec_enable_button->set_sensitive (false);
 	} else {
 		rec_enable_button->set_sensitive (true);
@@ -1420,7 +1419,7 @@ RouteUI::open_remote_control_id_dialog ()
 {
 	ArdourDialog dialog (_("Remote Control ID"));
 
-	uint32_t const limit = _session.ntracks() + _session.nbusses () + 4;
+	uint32_t const limit = _session->ntracks() + _session->nbusses () + 4;
 
 	HBox* hbox = manage (new HBox);
 	hbox->set_spacing (6);
diff --git a/gtk2_ardour/route_ui.h b/gtk2_ardour/route_ui.h
index 21d335ef79..a4d7e43b7d 100644
--- a/gtk2_ardour/route_ui.h
+++ b/gtk2_ardour/route_ui.h
@@ -23,6 +23,8 @@
 #include <list>
 
 #include "pbd/xml++.h"
+#include "pbd/scoped_connections.h"
+
 #include "ardour/ardour.h"
 #include "ardour/mute_master.h"
 #include "ardour/session_event.h"
@@ -49,8 +51,8 @@ class BindableToggleButton;
 class RouteUI : public virtual AxisView
 {
   public:
-	RouteUI(ARDOUR::Session&);
-	RouteUI(boost::shared_ptr<ARDOUR::Route>, ARDOUR::Session&);
+	RouteUI(ARDOUR::Session*);
+	RouteUI(boost::shared_ptr<ARDOUR::Route>, ARDOUR::Session*);
 
 	virtual ~RouteUI();
 
@@ -194,16 +196,18 @@ class RouteUI : public virtual AxisView
 	static int solo_visual_state (boost::shared_ptr<ARDOUR::Route>);
 	static int solo_visual_state_with_isolate (boost::shared_ptr<ARDOUR::Route>);
 	static int solo_isolate_visual_state (boost::shared_ptr<ARDOUR::Route>);
-	static int mute_visual_state (ARDOUR::Session &, boost::shared_ptr<ARDOUR::Route>);
+	static int mute_visual_state (ARDOUR::Session*, boost::shared_ptr<ARDOUR::Route>);
 
    protected:
- 	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList connections;
+	boost::signals2::scoped_connection route_going_away_connection;
 	bool self_destruct;
 
  	void init ();
  	void reset ();
 
 	void queue_route_group_op (ARDOUR::RouteGroup::Property prop, void (ARDOUR::Session::*session_method)(boost::shared_ptr<ARDOUR::RouteList>, bool), bool yn);
+	void self_delete ();
 
   private:
 	void check_rec_enable_sensitivity ();
@@ -225,6 +229,7 @@ class RouteUI : public virtual AxisView
 
 	SoloMuteRelease* _solo_release;
 	SoloMuteRelease* _mute_release;
+
 };
 
 #endif /* __ardour_route_ui__ */
diff --git a/gtk2_ardour/selection.cc b/gtk2_ardour/selection.cc
index da706a34d7..d2f1a67476 100644
--- a/gtk2_ardour/selection.cc
+++ b/gtk2_ardour/selection.cc
@@ -45,6 +45,7 @@ struct AudioRangeComparator {
     }
 };
 
+#if 0
 Selection&
 Selection::operator= (const Selection& other)
 {
@@ -58,6 +59,7 @@ Selection::operator= (const Selection& other)
 	}
 	return *this;
 }
+#endif
 
 bool
 operator== (const Selection& a, const Selection& b)
@@ -207,7 +209,7 @@ Selection::toggle (TimeAxisView* track)
 
 	if ((i = find (tracks.begin(), tracks.end(), track)) == tracks.end()) {
 		void (Selection::*pmf)(TimeAxisView*) = &Selection::remove;
-		track->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, pmf), track));
+		track->GoingAway.connect (boost::bind (pmf, this, track));
 		tracks.push_back (track);
 	} else {
 		tracks.erase (i);
@@ -336,7 +338,7 @@ Selection::add (const TrackViewList& track_list)
 
 	for (list<TimeAxisView*>::const_iterator i = added.begin(); i != added.end(); ++i) {
 		void (Selection::*pmf)(TimeAxisView*) = &Selection::remove;
-		(*i)->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, pmf), (*i)));
+		scoped_connect ((*i)->GoingAway, boost::bind (pmf, this, (*i)));
 	}
 
 	if (!added.empty()) {
@@ -947,7 +949,7 @@ Selection::add (Marker* m)
 
 		void (Selection::*pmf)(Marker*) = &Selection::remove;
 
-		m->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, pmf), m));
+		scoped_connect (m->GoingAway, boost::bind (pmf, this, m));
 
 		markers.push_back (m);
 		MarkersChanged();
diff --git a/gtk2_ardour/selection.h b/gtk2_ardour/selection.h
index f95b1dbfbe..739d3b4c01 100644
--- a/gtk2_ardour/selection.h
+++ b/gtk2_ardour/selection.h
@@ -25,6 +25,8 @@
 
 #include <sigc++/signal.h>
 
+#include "pbd/scoped_connections.h"
+
 #include "time_selection.h"
 #include "region_selection.h"
 #include "track_selection.h"
@@ -57,7 +59,7 @@ namespace Evoral {
 
 /** The Selection class holds lists of selected items (tracks, regions, etc. etc.). */
 
-class Selection : public sigc::trackable
+class Selection : public sigc::trackable, public PBD::ScopedConnectionList
 {
   public:
 	enum SelectionType {
@@ -86,7 +88,7 @@ class Selection : public sigc::trackable
 		clear();
 	}
 
-	Selection& operator= (const Selection& other);
+	// Selection& operator= (const Selection& other);
 
 	sigc::signal<void> RegionsChanged;
 	sigc::signal<void> TracksChanged;
@@ -185,9 +187,10 @@ class Selection : public sigc::trackable
 	template<class A> void foreach_region (void (ARDOUR::Region::*method)(A), A arg);
 
   private:
+	Selection (const Selection& other) {}
 	PublicEditor const * editor;
 	uint32_t next_time_id;
-
+	
 	void add (std::vector<AutomationSelectable*>&);
 };
 
diff --git a/gtk2_ardour/send_ui.cc b/gtk2_ardour/send_ui.cc
index 98dfab5860..1617ccd96a 100644
--- a/gtk2_ardour/send_ui.cc
+++ b/gtk2_ardour/send_ui.cc
@@ -34,11 +34,10 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-SendUI::SendUI (Gtk::Window* parent, boost::shared_ptr<Send> s, Session& se)
+SendUI::SendUI (Gtk::Window* parent, boost::shared_ptr<Send> s, Session* session)
 	: _send (s)
-	, _session (se)
-	, _gpm (se, 250)
-	, _panners (se)
+	, _gpm (session, 250)
+	, _panners (session)
 {
  	_panners.set_panner (s->panner());
  	_gpm.set_controls (boost::shared_ptr<Route>(), s->meter(), s->amp());
@@ -52,7 +51,7 @@ SendUI::SendUI (Gtk::Window* parent, boost::shared_ptr<Send> s, Session& se)
 	_vbox.pack_start (_hbox, false, false, false);
 	_vbox.pack_start (_panners, false, false);
 
-	io = manage (new IOSelector (parent, &se, s->output()));
+	io = manage (new IOSelector (parent, session, s->output()));
 
 	pack_start (_vbox, false, false);
 
@@ -119,10 +118,10 @@ SendUI::fast_update ()
 	}
 }
 
-SendUIWindow::SendUIWindow (boost::shared_ptr<Send> s, Session& ss)
+SendUIWindow::SendUIWindow (boost::shared_ptr<Send> s, Session* session)
 	: ArdourDialog (string("Ardour: send ") + s->name())
 {
-	ui = new SendUI (this, s, ss);
+	ui = new SendUI (this, s, session);
 
 	hpacker.pack_start (*ui, true, true);
 
@@ -131,8 +130,7 @@ SendUIWindow::SendUIWindow (boost::shared_ptr<Send> s, Session& ss)
 
 	set_name ("SendUIWindow");
 
-	going_away_connection = s->GoingAway.connect (
-			sigc::mem_fun (*this, &SendUIWindow::send_going_away));
+	going_away_connection = s->GoingAway.connect (sigc::mem_fun (*this, &SendUIWindow::send_going_away));
 
 	signal_delete_event().connect (sigc::bind (
 					       sigc::ptr_fun (just_hide_it),
@@ -148,7 +146,7 @@ void
 SendUIWindow::send_going_away ()
 {
 	ENSURE_GUI_THREAD (*this, &SendUIWindow::send_going_away)
-	delete_when_idle (this);
 	going_away_connection.disconnect ();
+	delete_when_idle (this);
 }
 
diff --git a/gtk2_ardour/send_ui.h b/gtk2_ardour/send_ui.h
index df5a8a216e..16543140a8 100644
--- a/gtk2_ardour/send_ui.h
+++ b/gtk2_ardour/send_ui.h
@@ -26,7 +26,6 @@
 
 namespace ARDOUR {
 	class Send;
-	class Session;
 	class IOProcessor;
 }
 
@@ -35,7 +34,7 @@ class IOSelector;
 class SendUI : public Gtk::HBox
 {
   public:
-	SendUI (Gtk::Window *, boost::shared_ptr<ARDOUR::Send>, ARDOUR::Session&);
+	SendUI (Gtk::Window *, boost::shared_ptr<ARDOUR::Send>, ARDOUR::Session*);
 	~SendUI();
 
 	void update ();
@@ -47,7 +46,6 @@ class SendUI : public Gtk::HBox
 
   private:
 	boost::shared_ptr<ARDOUR::Send> _send;
-	ARDOUR::Session&                _session;
 	GainMeter                       _gpm;
 	PannerUI                        _panners;
 	Gtk::VBox                       _vbox;
@@ -63,7 +61,7 @@ class SendUI : public Gtk::HBox
 class SendUIWindow : public ArdourDialog
 {
   public:
-	SendUIWindow(boost::shared_ptr<ARDOUR::Send>, ARDOUR::Session&);
+	SendUIWindow(boost::shared_ptr<ARDOUR::Send>, ARDOUR::Session*);
 	~SendUIWindow();
 
 	SendUI* ui;
@@ -72,7 +70,7 @@ class SendUIWindow : public ArdourDialog
 	Gtk::HBox hpacker;
 
 	void send_going_away ();
-	sigc::connection going_away_connection;
+	boost::signals2::scoped_connection going_away_connection;
 };
 
 #endif /* __ardour_gtk_send_ui_h__ */
diff --git a/gtk2_ardour/session_import_dialog.cc b/gtk2_ardour/session_import_dialog.cc
index 5511a0d68f..4b5793271b 100644
--- a/gtk2_ardour/session_import_dialog.cc
+++ b/gtk2_ardour/session_import_dialog.cc
@@ -36,11 +36,12 @@
 using namespace std;
 using namespace ARDOUR;
 
-SessionImportDialog::SessionImportDialog (ARDOUR::Session & target) :
+SessionImportDialog::SessionImportDialog (ARDOUR::Session* target) :
   ArdourDialog (_("Import from session")),
-  target (target),
   file_browse_button (_("Browse"))
 {
+	set_session (target);
+
 	// File entry
 	file_entry.set_name ("ImportFileNameEntry");
 	file_entry.set_text ("/");
@@ -101,24 +102,26 @@ SessionImportDialog::SessionImportDialog (ARDOUR::Session & target) :
 void
 SessionImportDialog::load_session (const string& filename)
 {
-	tree.read (filename);
-	boost::shared_ptr<AudioRegionImportHandler> region_handler (new AudioRegionImportHandler (tree, target));
-	boost::shared_ptr<AudioPlaylistImportHandler> pl_handler (new AudioPlaylistImportHandler (tree, target, *region_handler));
-
-	handlers.push_back (boost::static_pointer_cast<ElementImportHandler> (region_handler));
-	handlers.push_back (boost::static_pointer_cast<ElementImportHandler> (pl_handler));
-	handlers.push_back (HandlerPtr(new UnusedAudioPlaylistImportHandler (tree, target, *region_handler)));
-	handlers.push_back (HandlerPtr(new AudioTrackImportHandler (tree, target, *pl_handler)));
-	handlers.push_back (HandlerPtr(new LocationImportHandler (tree, target)));
-	handlers.push_back (HandlerPtr(new TempoMapImportHandler (tree, target)));
-
-	fill_list();
-
-	if (ElementImportHandler::dirty()) {
-		// Warn user
-		string txt = _("Some elements had errors in them. Please see the log for details");
-		Gtk::MessageDialog msg (txt, false, Gtk::MESSAGE_WARNING, Gtk::BUTTONS_OK, true);
-		msg.run();
+	if (_session) {
+		tree.read (filename);
+		boost::shared_ptr<AudioRegionImportHandler> region_handler (new AudioRegionImportHandler (tree, *_session));
+		boost::shared_ptr<AudioPlaylistImportHandler> pl_handler (new AudioPlaylistImportHandler (tree, *_session, *region_handler));
+		
+		handlers.push_back (boost::static_pointer_cast<ElementImportHandler> (region_handler));
+		handlers.push_back (boost::static_pointer_cast<ElementImportHandler> (pl_handler));
+		handlers.push_back (HandlerPtr(new UnusedAudioPlaylistImportHandler (tree, *_session, *region_handler)));
+		handlers.push_back (HandlerPtr(new AudioTrackImportHandler (tree, *_session, *pl_handler)));
+		handlers.push_back (HandlerPtr(new LocationImportHandler (tree, *_session)));
+		handlers.push_back (HandlerPtr(new TempoMapImportHandler (tree, *_session)));
+		
+		fill_list();
+		
+		if (ElementImportHandler::dirty()) {
+			// Warn user
+			string txt = _("Some elements had errors in them. Please see the log for details");
+			Gtk::MessageDialog msg (txt, false, Gtk::MESSAGE_WARNING, Gtk::BUTTONS_OK, true);
+			msg.run();
+		}
 	}
 }
 
diff --git a/gtk2_ardour/session_import_dialog.h b/gtk2_ardour/session_import_dialog.h
index 4144d07c88..01cbb6c0cc 100644
--- a/gtk2_ardour/session_import_dialog.h
+++ b/gtk2_ardour/session_import_dialog.h
@@ -48,7 +48,7 @@ class SessionImportDialog : public ArdourDialog
 	typedef std::list<ElementPtr> ElementList;
 
   public:
-	SessionImportDialog (ARDOUR::Session & target);
+	SessionImportDialog (ARDOUR::Session* target);
 
 	virtual Gtk::FileChooserAction browse_action() const { return Gtk::FILE_CHOOSER_ACTION_OPEN; }
 
@@ -68,7 +68,6 @@ class SessionImportDialog : public ArdourDialog
 	// Data
 	HandlerList        handlers;
 	XMLTree            tree;
-	ARDOUR::Session   &target;
 
 	// GUI
 	Gtk::Frame                    file_frame;
diff --git a/gtk2_ardour/session_metadata_dialog.cc b/gtk2_ardour/session_metadata_dialog.cc
index 6feec36fdf..0bce776c62 100644
--- a/gtk2_ardour/session_metadata_dialog.cc
+++ b/gtk2_ardour/session_metadata_dialog.cc
@@ -216,7 +216,6 @@ NumberMetadataField::str_to_uint (ustring const & str) const
 SessionMetadataSet::SessionMetadataSet (ustring const & name) :
   name (name)
 {
-	session = 0;
 }
 
 void
@@ -247,9 +246,13 @@ SessionMetadataSetEditable::get_tab_widget ()
 void
 SessionMetadataSetEditable::set_session (ARDOUR::Session * s)
 {
-	session = s;
+	SessionHandlePtr::set_session (s);
 
-	ARDOUR::SessionMetadata const & data = session->metadata();
+	if (!_session) {
+		return;
+	}
+
+	ARDOUR::SessionMetadata const & data = _session->metadata();
 
 	table.resize (list.size(), 2);
 	uint32_t row = 0;
@@ -266,7 +269,7 @@ SessionMetadataSetEditable::set_session (ARDOUR::Session * s)
 void
 SessionMetadataSetEditable::save_data ()
 {
-	ARDOUR::SessionMetadata & data = session->metadata();
+	ARDOUR::SessionMetadata & data = _session->metadata();
 	for (DataList::const_iterator it = list.begin(); it != list.end(); ++it) {
 		(*it)->save_data(data);
 	}
@@ -300,8 +303,6 @@ SessionMetadataSetImportable::SessionMetadataSetImportable (ustring const & name
 	tree_view.append_column (*viewcol);
 
 	select_all_check.signal_toggled().connect (sigc::mem_fun(*this, &SessionMetadataSetImportable::select_all));
-
-	session = 0;
 }
 
 Gtk::Widget &
@@ -321,12 +322,12 @@ SessionMetadataSetImportable::get_select_all_widget ()
 void
 SessionMetadataSetImportable::load_extra_data (ARDOUR::SessionMetadata const & data)
 {
-	if (!session) {
+	if (!_session) {
 		std::cerr << "Programming error: no session set for SessionMetaDataSetImportable (in load_data)!" << std::endl;
 		return;
 	}
 
-	ARDOUR::SessionMetadata & session_data = session->metadata();
+	ARDOUR::SessionMetadata & session_data = _session->metadata();
 
 	MetadataPtr session_field;
 	MetadataPtr import_field;
@@ -369,12 +370,12 @@ SessionMetadataSetImportable::load_extra_data (ARDOUR::SessionMetadata const & d
 void
 SessionMetadataSetImportable::save_data ()
 {
-	if (!session) {
+	if (!_session) {
 		std::cerr << "Programming error: no session set for SessionMetaDataSetImportable (in import_data)!" << std::endl;
 		return;
 	}
 
-	ARDOUR::SessionMetadata & session_data = session->metadata();
+	ARDOUR::SessionMetadata & session_data = _session->metadata();
 
 	Gtk::TreeModel::Children fields = tree->children();
 	Gtk::TreeModel::Children::iterator it;
@@ -425,7 +426,7 @@ template <typename DataSet>
 void
 SessionMetadataDialog<DataSet>::init_data ()
 {
-	if (!session) {
+	if (!_session) {
 		std::cerr << "Programming error: no session set for SessionMetaDataDialog (in init_data)!" << std::endl;
 		return;
 	}
@@ -435,7 +436,7 @@ SessionMetadataDialog<DataSet>::init_data ()
 	init_people_data ();
 
 	for (DataSetList::iterator it = data_list.begin(); it != data_list.end(); ++it) {
-		(*it)->set_session (session);
+		(*it)->set_session (_session);
 
 		notebook.append_page ((*it)->get_widget(), (*it)->get_tab_widget());
 	}
@@ -659,7 +660,7 @@ SessionMetadataImporter::~SessionMetadataImporter ()
 void
 SessionMetadataImporter::run ()
 {
-	if (!session) {
+	if (!_session) {
 		std::cerr << "Programming error: no session set for SessionMetaDataImporter (in run)!" << std::endl;
 		return;
 	}
diff --git a/gtk2_ardour/session_metadata_dialog.h b/gtk2_ardour/session_metadata_dialog.h
index 3e618c079f..be64c90ae9 100644
--- a/gtk2_ardour/session_metadata_dialog.h
+++ b/gtk2_ardour/session_metadata_dialog.h
@@ -117,15 +117,13 @@ class NumberMetadataField : public MetadataField {
 };
 
 /// Interface for MetadataFields
-class SessionMetadataSet {
+class SessionMetadataSet : public ARDOUR::SessionHandlePtr {
   public:
 	SessionMetadataSet (Glib::ustring const & name);
 	virtual ~SessionMetadataSet () {};
 
 	void add_data_field (MetadataPtr field);
 
-	/// Sets session, into which the data is eventually saved
-	virtual void set_session (ARDOUR::Session * s) { session = s; }
 	/// allows loading extra data into data sets (for importing etc.)
 	virtual void load_extra_data (ARDOUR::SessionMetadata const & /*data*/) { }
 	/// Saves data to session
@@ -138,7 +136,6 @@ class SessionMetadataSet {
 	typedef std::list<MetadataPtr> DataList;
 	DataList list;
 	Glib::ustring name;
-	ARDOUR::Session *session;
 };
 
 /// Contains MetadataFields for editing
diff --git a/gtk2_ardour/sfdb_ui.cc b/gtk2_ardour/sfdb_ui.cc
index 05eacd1367..6919be9f62 100644
--- a/gtk2_ardour/sfdb_ui.cc
+++ b/gtk2_ardour/sfdb_ui.cc
@@ -113,8 +113,7 @@ importmode2string (ImportMode mode)
 }
 
 SoundFileBox::SoundFileBox (bool persistent)
-	: _session(0),
-	  table (6, 2),
+	: table (6, 2),
 	  length_clock ("sfboxLengthClock", !persistent, "EditCursorClock", false, false, true, false),
 	  timecode_clock ("sfboxTimecodeClock", !persistent, "EditCursorClock", false, false, false, false),
 	  main_box (false, 6),
@@ -202,16 +201,15 @@ SoundFileBox::SoundFileBox (bool persistent)
 void
 SoundFileBox::set_session(Session* s)
 {
-	_session = s;
+	SessionHandlePtr::set_session (s);
+
+	length_clock.set_session (s);
+	timecode_clock.set_session (s);
 
 	if (!_session) {
 		play_btn.set_sensitive (false);
 		stop_btn.set_sensitive (false);
 	}
-
-
-	length_clock.set_session (s);
-	timecode_clock.set_session (s);
 }
 
 bool
@@ -582,7 +580,8 @@ SoundFileBrowser::set_session (Session* s)
 {
 	ArdourDialog::set_session (s);
 	preview.set_session (s);
-	if (s) {
+
+	if (_session) {
 		add_gain_meter ();
 	} else {
 		remove_gain_meter ();
@@ -594,9 +593,9 @@ SoundFileBrowser::add_gain_meter ()
 {
 	delete gm;
 
-	gm = new GainMeter (*session, 250);
+	gm = new GainMeter (_session, 250);
 
-	boost::shared_ptr<Route> r = session->the_auditioner ();
+	boost::shared_ptr<Route> r = _session->the_auditioner ();
 
 	gm->set_controls (r, r->shared_peak_meter(), r->amp());
 
@@ -633,7 +632,7 @@ SoundFileBrowser::stop_metering ()
 void
 SoundFileBrowser::meter ()
 {
-	if (is_mapped () && session && gm) {
+	if (is_mapped () && _session && gm) {
 		gm->update_meters ();
 	}
 }
@@ -906,7 +905,7 @@ SoundFileOmega::reset_options ()
 	bool same_size;
 	bool src_needed;
 	bool selection_includes_multichannel;
-	bool selection_can_be_embedded_with_links = check_link_status (*session, paths);
+	bool selection_can_be_embedded_with_links = check_link_status (_session, paths);
 	ImportMode mode;
 
 	if (check_info (paths, same_size, src_needed, selection_includes_multichannel)) {
@@ -1100,7 +1099,7 @@ SoundFileOmega::check_info (const vector<ustring>& paths, bool& same_size, bool&
 				}
 			}
 
-			if ((nframes_t) info.samplerate != session->frame_rate()) {
+			if ((nframes_t) info.samplerate != _session->frame_rate()) {
 				src_needed = true;
 			}
 
@@ -1126,9 +1125,9 @@ SoundFileOmega::check_info (const vector<ustring>& paths, bool& same_size, bool&
 
 
 bool
-SoundFileOmega::check_link_status (const Session& s, const vector<ustring>& paths)
+SoundFileOmega::check_link_status (const Session* s, const vector<ustring>& paths)
 {
-	sys::path path = s.session_directory().sound_path() / "linktest";
+	sys::path path = s->session_directory().sound_path() / "linktest";
 	string tmpdir = path.to_string();
 	bool ret = false;
 
@@ -1174,8 +1173,8 @@ SoundFileChooser::on_hide ()
 	ArdourDialog::on_hide();
 	stop_metering ();
 
-	if (session) {
-		session->cancel_audition();
+	if (_session) {
+		_session->cancel_audition();
 	}
 }
 
@@ -1360,8 +1359,8 @@ void
 SoundFileOmega::on_hide ()
 {
 	ArdourDialog::on_hide();
-	if (session) {
-		session->cancel_audition();
+	if (_session) {
+		_session->cancel_audition();
 	}
 }
 
diff --git a/gtk2_ardour/sfdb_ui.h b/gtk2_ardour/sfdb_ui.h
index c3030669c2..15affab570 100644
--- a/gtk2_ardour/sfdb_ui.h
+++ b/gtk2_ardour/sfdb_ui.h
@@ -39,6 +39,7 @@
 #include <gtkmm/textview.h>
 
 #include "ardour/audiofilesource.h"
+#include "ardour/session_handle.h"
 
 #include "ardour_dialog.h"
 #include "editing.h"
@@ -50,7 +51,7 @@ namespace ARDOUR {
 
 class GainMeter;
 
-class SoundFileBox : public Gtk::VBox
+class SoundFileBox : public Gtk::VBox, public ARDOUR::SessionHandlePtr
 {
   public:
 	SoundFileBox (bool persistent);
@@ -64,7 +65,6 @@ class SoundFileBox : public Gtk::VBox
 	bool autoplay () const;
 
   protected:
-	ARDOUR::Session* _session;
 	Glib::ustring path;
 
 	ARDOUR::SoundFileInfo sf_info;
@@ -241,7 +241,7 @@ class SoundFileOmega : public SoundFileBrowser
 	bool check_info (const std::vector<Glib::ustring>& paths,
 			 bool& same_size, bool& src_needed, bool& multichannel);
 
-	static bool check_link_status (const ARDOUR::Session&, const std::vector<Glib::ustring>& paths);
+	static bool check_link_status (const ARDOUR::Session*, const std::vector<Glib::ustring>& paths);
 
 	void file_selection_changed ();
 	bool reset_options ();
diff --git a/gtk2_ardour/streamview.cc b/gtk2_ardour/streamview.cc
index 168ddb3904..626e2bf537 100644
--- a/gtk2_ardour/streamview.cc
+++ b/gtk2_ardour/streamview.cc
@@ -79,16 +79,12 @@ StreamView::StreamView (RouteTimeAxisView& tv, ArdourCanvas::Group* group)
 			canvas_rect, &_trackview));
 
 	if (_trackview.is_track()) {
-		_trackview.track()->DiskstreamChanged.connect (
-				sigc::mem_fun (*this, &StreamView::diskstream_changed));
-		_trackview.session().TransportStateChange.connect (
-				sigc::mem_fun (*this, &StreamView::transport_changed));
-		_trackview.session().TransportLooped.connect (
-				sigc::mem_fun (*this, &StreamView::transport_looped));
-		_trackview.get_diskstream()->RecordEnableChanged.connect (
-				sigc::mem_fun (*this, &StreamView::rec_enable_changed));
-		_trackview.session().RecordStateChanged.connect (
-				sigc::mem_fun (*this, &StreamView::sess_rec_enable_changed));
+		scoped_connect (_trackview.track()->DiskstreamChanged, boost::bind (&StreamView::diskstream_changed, this));
+		scoped_connect (_trackview.get_diskstream()->RecordEnableChanged, boost::bind (&StreamView::rec_enable_changed, this));
+
+		scoped_connect (_trackview.session()->TransportStateChange, boost::bind (&StreamView::transport_changed, this));
+		scoped_connect (_trackview.session()->TransportLooped, boost::bind (&StreamView::transport_looped, this));
+		scoped_connect (_trackview.session()->RecordStateChanged, boost::bind (&StreamView::sess_rec_enable_changed, this));
 	}
 
 	ColorsChanged.connect (sigc::mem_fun (*this, &StreamView::color_handler));
@@ -96,6 +92,8 @@ StreamView::StreamView (RouteTimeAxisView& tv, ArdourCanvas::Group* group)
 
 StreamView::~StreamView ()
 {
+	cerr << "Streamview " << _trackview.name() << " deleted\n";
+
 	undisplay_diskstream ();
 
 	delete canvas_rect;
@@ -210,6 +208,7 @@ StreamView::remove_region_view (boost::weak_ptr<Region> weak_r)
 		if (((*i)->region()) == r) {
 			RegionView* rv = *i;
 			region_views.erase (i);
+			cerr << "Deleting RV for " << r->name() << " @ " << r << endl;
 			delete rv;
 			break;
 		}
@@ -234,9 +233,7 @@ StreamView::display_diskstream (boost::shared_ptr<Diskstream> ds)
 {
 	playlist_change_connection.disconnect();
 	playlist_changed (ds);
-	playlist_change_connection = ds->PlaylistChanged.connect (
-		sigc::bind (sigc::mem_fun (*this, &StreamView::playlist_changed_weak),
-			    boost::weak_ptr<Diskstream> (ds)));
+	playlist_change_connection = ds->PlaylistChanged.connect (boost::bind (&StreamView::playlist_changed_weak, this, boost::weak_ptr<Diskstream> (ds)));
 }
 
 void
@@ -342,12 +339,7 @@ StreamView::playlist_changed (boost::shared_ptr<Diskstream> ds)
 
 	/* disconnect from old playlist */
 
-	for (vector<sigc::connection>::iterator i = playlist_connections.begin();
-			i != playlist_connections.end(); ++i) {
-		(*i).disconnect();
-	}
-
-	playlist_connections.clear();
+	playlist_connections.drop_connections ();
 	undisplay_diskstream ();
 
 	/* update layers count and the y positions and heights of our regions */
@@ -363,14 +355,9 @@ StreamView::playlist_changed (boost::shared_ptr<Diskstream> ds)
 
 	/* catch changes */
 
-	playlist_connections.push_back (ds->playlist()->Modified.connect (sigc::bind (
-	 		sigc::mem_fun (*this, &StreamView::playlist_modified_weak), ds)));
-
-	playlist_connections.push_back (ds->playlist()->RegionAdded.connect (
-			sigc::mem_fun (*this, &StreamView::add_region_view_weak)));
-
-	playlist_connections.push_back (ds->playlist()->RegionRemoved.connect (
-			sigc::mem_fun (*this, &StreamView::remove_region_view)));
+	playlist_connections.add_connection (ds->playlist()->Modified.connect (boost::bind (&StreamView::playlist_modified_weak, this, ds)));
+	playlist_connections.add_connection (ds->playlist()->RegionAdded.connect (boost::bind (&StreamView::add_region_view_weak, this, _1)));
+	playlist_connections.add_connection (ds->playlist()->RegionRemoved.connect (boost::bind (&StreamView::remove_region_view, this, _1)));
 }
 
 void
diff --git a/gtk2_ardour/streamview.h b/gtk2_ardour/streamview.h
index 3b715ff099..0fe0b1a9ed 100644
--- a/gtk2_ardour/streamview.h
+++ b/gtk2_ardour/streamview.h
@@ -22,6 +22,8 @@
 #include <list>
 #include <cmath>
 
+#include "pbd/scoped_connections.h"
+
 #include "ardour/location.h"
 #include "enums.h"
 #include "simplerect.h"
@@ -53,7 +55,7 @@ class RegionSelection;
 class CrossfadeView;
 class Selection;
 
-class StreamView : public sigc::trackable
+class StreamView : public sigc::trackable, public PBD::ScopedConnectionList
 {
 public:
 	virtual ~StreamView ();
@@ -158,16 +160,16 @@ protected:
 	Gdk::Color region_color;      ///< Contained region color
 	uint32_t   stream_base_color; ///< Background color
 
-	std::vector<sigc::connection> playlist_connections;
-	sigc::connection         playlist_change_connection;
+	PBD::ScopedConnectionList playlist_connections;
+	boost::signals2::scoped_connection playlist_change_connection;
 
 	ARDOUR::layer_t _layers;
 	LayerDisplay    _layer_display;
 
 	double height;
 
-	std::list<sigc::connection> rec_data_ready_connections;
-	nframes_t                   last_rec_data_frame;
+	PBD::ScopedConnectionList rec_data_ready_connections;
+	nframes_t                 last_rec_data_frame;
 
 private:
 	void update_coverage_frames ();
diff --git a/gtk2_ardour/strip_silence_dialog.cc b/gtk2_ardour/strip_silence_dialog.cc
index 6872e16455..ab1297d6bc 100644
--- a/gtk2_ardour/strip_silence_dialog.cc
+++ b/gtk2_ardour/strip_silence_dialog.cc
@@ -129,7 +129,7 @@ StripSilenceDialog::create_waves ()
 	int n = 0;
 
 	for (std::list<Wave>::iterator i = _waves.begin(); i != _waves.end(); ++i) {
-		if (i->region->audio_source(0)->peaks_ready (sigc::mem_fun (*this, &StripSilenceDialog::peaks_ready), _peaks_ready_connection)) {
+		if (i->region->audio_source(0)->peaks_ready (boost::bind (&StripSilenceDialog::peaks_ready, this), _peaks_ready_connection)) {
 			i->view = new WaveView (*(_canvas->root()));
 			i->view->property_data_src() = static_cast<gpointer>(i->region.get());
 			i->view->property_cache() = WaveView::create_cache ();
diff --git a/gtk2_ardour/strip_silence_dialog.h b/gtk2_ardour/strip_silence_dialog.h
index b7f776b537..f79abb8eb9 100644
--- a/gtk2_ardour/strip_silence_dialog.h
+++ b/gtk2_ardour/strip_silence_dialog.h
@@ -66,5 +66,5 @@ private:
 	int _wave_width;
 	int _wave_height;
 
-	sigc::connection _peaks_ready_connection;
+	boost::signals2::scoped_connection _peaks_ready_connection;
 };
diff --git a/gtk2_ardour/time_axis_view.cc b/gtk2_ardour/time_axis_view.cc
index b8d7b3b9e0..e1368dc5f3 100644
--- a/gtk2_ardour/time_axis_view.cc
+++ b/gtk2_ardour/time_axis_view.cc
@@ -74,7 +74,7 @@ uint32_t TimeAxisView::hSmall = 0;
 bool TimeAxisView::need_size_info = true;
 int const TimeAxisView::_max_order = 512;
 
-TimeAxisView::TimeAxisView (ARDOUR::Session& sess, PublicEditor& ed, TimeAxisView* rent, Canvas& /*canvas*/)
+TimeAxisView::TimeAxisView (ARDOUR::Session* sess, PublicEditor& ed, TimeAxisView* rent, Canvas& /*canvas*/)
 	: AxisView (sess),
 	  controls_table (2, 8),
 	  _y_position (0),
@@ -924,7 +924,7 @@ TimeAxisView::add_ghost (RegionView* rv)
 
 	if(gr) {
 		ghosts.push_back(gr);
-		gr->GoingAway.connect (sigc::mem_fun(*this, &TimeAxisView::erase_ghost));
+		scoped_connect (gr->GoingAway, boost::bind (&TimeAxisView::erase_ghost, this, _1));
 	}
 }
 
diff --git a/gtk2_ardour/time_axis_view.h b/gtk2_ardour/time_axis_view.h
index e8860cb907..67aaa0d327 100644
--- a/gtk2_ardour/time_axis_view.h
+++ b/gtk2_ardour/time_axis_view.h
@@ -34,6 +34,7 @@
 #include <gtkmm2ext/focus_entry.h>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/types.h"
 #include "ardour/region.h"
@@ -89,7 +90,7 @@ class TimeAxisView : public virtual AxisView, public PBD::Stateful
 	static uint32_t hSmaller;
 	static uint32_t hSmall;
 
-	TimeAxisView(ARDOUR::Session& sess, PublicEditor& ed, TimeAxisView* parent, ArdourCanvas::Canvas& canvas);
+	TimeAxisView(ARDOUR::Session* sess, PublicEditor& ed, TimeAxisView* parent, ArdourCanvas::Canvas& canvas);
 	virtual ~TimeAxisView ();
 
 	XMLNode& get_state ();
diff --git a/gtk2_ardour/time_axis_view_item.h b/gtk2_ardour/time_axis_view_item.h
index de8d3792db..1dd16043ad 100644
--- a/gtk2_ardour/time_axis_view_item.h
+++ b/gtk2_ardour/time_axis_view_item.h
@@ -25,6 +25,8 @@
 
 #include <libgnomecanvasmm/pixbuf.h>
 
+#include "pbd/scoped_connections.h"
+
 #include "selectable.h"
 #include "simplerect.h"
 #include "canvas.h"
@@ -35,7 +37,7 @@ class TimeAxisView;
  * A base class for 'items' that may appear upon a TimeAxisView
  *
  */
-class TimeAxisViewItem : public Selectable
+class TimeAxisViewItem : public Selectable, public PBD::ScopedConnectionList
 {
    public:
 	virtual ~TimeAxisViewItem() ;
diff --git a/gtk2_ardour/visual_time_axis.cc b/gtk2_ardour/visual_time_axis.cc
index 1e83f56dc9..b4b613042b 100644
--- a/gtk2_ardour/visual_time_axis.cc
+++ b/gtk2_ardour/visual_time_axis.cc
@@ -65,7 +65,7 @@ using namespace Gtk;
  * @param sess the current session
  * @param canvas the parent canvas object
  */
-VisualTimeAxis::VisualTimeAxis(const string & name, PublicEditor& ed, ARDOUR::Session& sess, Canvas& canvas)
+VisualTimeAxis::VisualTimeAxis(const string & name, PublicEditor& ed, ARDOUR::Session* sess, Canvas& canvas)
 	: AxisView(sess),
 	  TimeAxisView(sess,ed,(TimeAxisView*) 0, canvas),
 	  visual_button (_("v")),
diff --git a/gtk2_ardour/visual_time_axis.h b/gtk2_ardour/visual_time_axis.h
index f728a1f4cf..9bc98fc345 100644
--- a/gtk2_ardour/visual_time_axis.h
+++ b/gtk2_ardour/visual_time_axis.h
@@ -145,7 +145,7 @@ class VisualTimeAxis : public TimeAxisView
 		 * @param sess the current session
 		 * @param canvas the parent canvas object
 		 */
-		VisualTimeAxis(const std::string & name, PublicEditor& ed, ARDOUR::Session& sess, ArdourCanvas::Canvas& canvas) ;
+		VisualTimeAxis(const std::string & name, PublicEditor& ed, ARDOUR::Session* sess, ArdourCanvas::Canvas& canvas) ;
 
 
 		//---------------------------------------------------------------------------------------//
diff --git a/libs/ardour/ardour/ardour.h b/libs/ardour/ardour/ardour.h
index a1b3d06f62..1333b58d6f 100644
--- a/libs/ardour/ardour/ardour.h
+++ b/libs/ardour/ardour/ardour.h
@@ -26,6 +26,8 @@
 #include <limits.h>
 #include <signal.h>
 
+#include <boost/signals2.hpp>
+
 #include "pbd/error.h"
 #include "pbd/failed_constructor.h"
 #include "pbd/locale_guard.h"
@@ -44,7 +46,7 @@ namespace ARDOUR {
 	class AudioEngine;
 
 	static const nframes_t max_frames = JACK_MAX_FRAMES;
-	extern sigc::signal<void,std::string> BootMessage;
+	extern boost::signals2::signal<void(std::string)> BootMessage;
 
 	int init (bool with_vst, bool try_optimization);
 	void init_post_engine ();
diff --git a/libs/ardour/ardour/audio_diskstream.h b/libs/ardour/ardour/audio_diskstream.h
index 838c9406ee..4d2209d79b 100644
--- a/libs/ardour/ardour/audio_diskstream.h
+++ b/libs/ardour/ardour/audio_diskstream.h
@@ -19,7 +19,6 @@
 #ifndef __ardour_audio_diskstream_h__
 #define __ardour_audio_diskstream_h__
 
-#include <sigc++/signal.h>
 
 #include <cmath>
 #include <string>
diff --git a/libs/ardour/ardour/audioengine.h b/libs/ardour/ardour/audioengine.h
index a9c414e566..ac367ddd64 100644
--- a/libs/ardour/ardour/audioengine.h
+++ b/libs/ardour/ardour/audioengine.h
@@ -26,17 +26,19 @@
 #include <exception>
 #include <string>
 
-#include <sigc++/signal.h>
 
 #include <glibmm/thread.h>
 
 #include "pbd/rcu.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/ardour.h"
 #include <jack/jack.h>
 #include <jack/transport.h>
-#include "ardour/types.h"
+
 #include "ardour/data_type.h"
+#include "ardour/session_handle.h"
+#include "ardour/types.h"
 
 namespace ARDOUR {
 
@@ -45,7 +47,7 @@ class MidiPort;
 class Port;
 class Session;
 
-class AudioEngine : public sigc::trackable
+class AudioEngine : public SessionHandlePtr
 {
    public:
 	typedef std::set<Port*> Ports;
@@ -110,7 +112,7 @@ class AudioEngine : public sigc::trackable
 	}
 
 	void set_session (Session *);
-	void remove_session ();
+	void remove_session (); // not a replacement for SessionHandle::session_going_away()
 
 	class PortRegistrationFailure : public std::exception {
 	public:
@@ -185,32 +187,32 @@ class AudioEngine : public sigc::trackable
 _	   the regular process() call to session->process() is not made.
 	*/
 
-	sigc::signal<int,nframes_t> Freewheel;
+	boost::signals2::signal<int(nframes_t)> Freewheel;
 
-	sigc::signal<void> Xrun;
+	boost::signals2::signal<void()> Xrun;
 
 	/* this signal is if JACK notifies us of a graph order event */
 
-	sigc::signal<void> GraphReordered;
+	boost::signals2::signal<void()> GraphReordered;
 
 	/* this signal is emitted if the sample rate changes */
 
-	sigc::signal<void,nframes_t> SampleRateChanged;
+	boost::signals2::signal<void(nframes_t)> SampleRateChanged;
 
 	/* this signal is sent if JACK ever disconnects us */
 
-	sigc::signal<void> Halted;
+	boost::signals2::signal<void()> Halted;
 
 	/* these two are emitted when the engine itself is
 	   started and stopped
 	*/
 
-	sigc::signal<void> Running;
-	sigc::signal<void> Stopped;
+	boost::signals2::signal<void()> Running;
+	boost::signals2::signal<void()> Stopped;
 
 	/* this signal is emitted if a JACK port is registered or unregistered */
 
-	sigc::signal<void> PortRegisteredOrUnregistered;
+	boost::signals2::signal<void()> PortRegisteredOrUnregistered;
 
 	std::string make_port_name_relative (std::string);
 	std::string make_port_name_non_relative (std::string);
@@ -221,7 +223,6 @@ _	   the regular process() call to session->process() is not made.
   private:
 	static AudioEngine*       _instance;
 
-	ARDOUR::Session*           session;
 	jack_client_t* volatile   _jack; /* could be reset to null by SIGPIPE or another thread */
 	std::string                jack_client_name;
 	Glib::Mutex               _process_lock;
@@ -241,7 +242,7 @@ _	   the regular process() call to session->process() is not made.
 	bool                      _freewheeling;
 	bool                      _freewheel_pending;
 	bool                      _freewheel_thread_registered;
-	sigc::slot<int,nframes_t>  freewheel_action;
+	boost::function<int(nframes_t)>  freewheel_action;
 	bool                       reconnect_on_halt;
 	int                       _usecs_per_cycle;
 
diff --git a/libs/ardour/ardour/audiofilesource.h b/libs/ardour/ardour/audiofilesource.h
index 6c04ebffb1..3312bc889d 100644
--- a/libs/ardour/ardour/audiofilesource.h
+++ b/libs/ardour/ardour/audiofilesource.h
@@ -84,7 +84,7 @@ public:
 	static void set_bwf_serial_number (int);
 	static void set_header_position_offset (nframes_t offset );
 
-	static sigc::signal<void> HeaderPositionOffsetChanged;
+	static boost::signals2::signal<void()> HeaderPositionOffsetChanged;
 
 protected:
 	/** Constructor to be called for existing external-to-session files */
diff --git a/libs/ardour/ardour/audioplaylist.h b/libs/ardour/ardour/audioplaylist.h
index 277fe5a8e1..927ccfbe11 100644
--- a/libs/ardour/ardour/audioplaylist.h
+++ b/libs/ardour/ardour/audioplaylist.h
@@ -52,9 +52,9 @@ class AudioPlaylist : public ARDOUR::Playlist
 
 	int set_state (const XMLNode&, int version);
 
-	sigc::signal<void,boost::shared_ptr<Crossfade> > NewCrossfade;
-
-	void foreach_crossfade (sigc::slot<void, boost::shared_ptr<Crossfade> >);
+	boost::signals2::signal<void(boost::shared_ptr<Crossfade>)>  NewCrossfade;
+	
+	void foreach_crossfade (boost::function<void (boost::shared_ptr<Crossfade>)>);
 	void crossfades_at (nframes_t frame, Crossfades&);
 
 	bool destroy_region (boost::shared_ptr<Region>);
diff --git a/libs/ardour/ardour/audiosource.h b/libs/ardour/ardour/audiosource.h
index 328a23ac19..dfa103f2e3 100644
--- a/libs/ardour/ardour/audiosource.h
+++ b/libs/ardour/ardour/audiosource.h
@@ -27,8 +27,7 @@
 
 #include <glibmm/thread.h>
 #include <glibmm/ustring.h>
-
-#include <sigc++/signal.h>
+#include <boost/function.hpp>
 
 #include "ardour/source.h"
 #include "ardour/ardour.h"
@@ -73,10 +72,10 @@ class AudioSource : virtual public Source,
 			sframes_t start, nframes_t cnt, double samples_per_visual_peak) const;
 
 	int  build_peaks ();
-	bool peaks_ready (sigc::slot<void>, sigc::connection&) const;
+	bool peaks_ready (boost::function<void()> callWhenReady, boost::signals2::connection& connection_established_if_not_ready) const;
 
-	mutable sigc::signal<void>  PeaksReady;
-	mutable sigc::signal<void,nframes_t,nframes_t>  PeakRangeReady;
+	mutable boost::signals2::signal<void()>  PeaksReady;
+	mutable boost::signals2::signal<void(nframes_t,nframes_t)>  PeakRangeReady;
 
 	XMLNode& get_state ();
 	int set_state (const XMLNode&, int version);
diff --git a/libs/ardour/ardour/automation_list.h b/libs/ardour/ardour/automation_list.h
index 69c8e38c95..c75abda0b7 100644
--- a/libs/ardour/ardour/automation_list.h
+++ b/libs/ardour/ardour/automation_list.h
@@ -24,7 +24,6 @@
 #include <list>
 #include <cmath>
 
-#include <sigc++/signal.h>
 #include <glibmm/thread.h>
 
 #include "pbd/undo.h"
@@ -57,11 +56,11 @@ class AutomationList : public PBD::StatefulDestructible, public Evoral::ControlL
 
 	void set_automation_state (AutoState);
 	AutoState automation_state() const { return _state; }
-	sigc::signal<void> automation_state_changed;
+	boost::signals2::signal<void()> automation_state_changed;
 
 	void set_automation_style (AutoStyle m);
 	AutoStyle automation_style() const { return _style; }
-	sigc::signal<void> automation_style_changed;
+	boost::signals2::signal<void()> automation_style_changed;
 
 	bool automation_playback() const {
 		return (_state & Play) || ((_state & Touch) && !_touching);
@@ -70,10 +69,10 @@ class AutomationList : public PBD::StatefulDestructible, public Evoral::ControlL
 		return (_state & Write) || ((_state & Touch) && _touching);
 	}
 
-	sigc::signal<void> StateChanged;
+	boost::signals2::signal<void()> StateChanged;
 
-	static sigc::signal<void, AutomationList*> AutomationListCreated;
-	mutable sigc::signal<void> Dirty;
+	static boost::signals2::signal<void(AutomationList*)> AutomationListCreated;
+	mutable boost::signals2::signal<void()> Dirty;
 
 	void start_touch ();
 	void stop_touch ();
diff --git a/libs/ardour/ardour/bundle.h b/libs/ardour/ardour/bundle.h
index 196b1f2a09..662c3799a5 100644
--- a/libs/ardour/ardour/bundle.h
+++ b/libs/ardour/ardour/bundle.h
@@ -23,8 +23,10 @@
 #include <string>
 #include <vector>
 #include <glibmm/thread.h>
-#include <sigc++/signal.h>
 #include <boost/shared_ptr.hpp>
+
+#include "pbd/scoped_connections.h"
+
 #include "ardour/data_type.h"
 
 namespace ARDOUR {
@@ -37,7 +39,7 @@ class AudioEngine;
  *  `Channel' is a rather overloaded term but I can't think of a better
  *  one right now.
  */
-class Bundle : public sigc::trackable
+class Bundle : public PBD::ScopedConnectionList
 {
   public:
 
@@ -118,7 +120,7 @@ class Bundle : public sigc::trackable
 		DirectionChanged = 0x10 ///< the direction (whether ports are inputs or outputs) has changed
 	};
 
-	sigc::signal<void, Change> Changed;
+	boost::signals2::signal<void(Change)> Changed;
 
   protected:
 
diff --git a/libs/ardour/ardour/butler.h b/libs/ardour/ardour/butler.h
index b88b820736..60697517fb 100644
--- a/libs/ardour/ardour/butler.h
+++ b/libs/ardour/ardour/butler.h
@@ -21,17 +21,18 @@
 #define __ardour_butler_h__
 
 #include <glibmm/thread.h>
+
 #include "ardour/types.h"
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 
-class Session;
-
-class Butler {
-public:
-	Butler(Session* session);
+class Butler : public SessionHandleRef
+{
+  public:
+	Butler (Session& session);
 	~Butler();
-
+	
 	int  start_thread();
 	void terminate_thread();
 	void schedule_transport_work();
@@ -58,7 +59,6 @@ public:
 		};
 	};
 
-	Session*     session;
 	pthread_t    thread;
 	Glib::Mutex  request_lock;
 	Glib::Cond   paused;
diff --git a/libs/ardour/ardour/configuration.h b/libs/ardour/ardour/configuration.h
index 02bbcaca23..1c82309d87 100644
--- a/libs/ardour/ardour/configuration.h
+++ b/libs/ardour/ardour/configuration.h
@@ -19,7 +19,9 @@
 
 #ifndef __ardour_configuration_h__
 #define __ardour_configuration_h__
+
 #include <boost/function.hpp>
+#include <boost/signals2.hpp>
 #include "pbd/stateful.h"
 #include "ardour/configuration_variable.h"
 
@@ -39,7 +41,7 @@ class Configuration : public PBD::Stateful
 	virtual XMLNode & get_variables () = 0;
 	virtual void set_variables (XMLNode const &) = 0;
 
-	sigc::signal<void, std::string> ParameterChanged;
+	boost::signals2::signal<void(std::string)> ParameterChanged;
 };
 
 } // namespace ARDOUR
diff --git a/libs/ardour/ardour/control_protocol_manager.h b/libs/ardour/ardour/control_protocol_manager.h
index d2b1796b18..6fedc95c6c 100644
--- a/libs/ardour/ardour/control_protocol_manager.h
+++ b/libs/ardour/ardour/control_protocol_manager.h
@@ -23,11 +23,11 @@
 #include <string>
 #include <list>
 
-#include <sigc++/sigc++.h>
 
 #include <glibmm/thread.h>
 
 #include "pbd/stateful.h"
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 
@@ -49,16 +49,16 @@ struct ControlProtocolInfo {
     ~ControlProtocolInfo() { if (state) { delete state; } }
 };
 
- class ControlProtocolManager : public sigc::trackable, public PBD::Stateful
+class ControlProtocolManager : public PBD::Stateful, public ARDOUR::SessionHandlePtr
 {
   public:
 	~ControlProtocolManager ();
 
 	static ControlProtocolManager& instance();
 
-	void set_session (Session&);
+	void set_session (Session*);
 	void discover_control_protocols ();
-	void foreach_known_protocol (sigc::slot<void,const ControlProtocolInfo*>);
+	void foreach_known_protocol (boost::function<void(const ControlProtocolInfo*)>);
 	void load_mandatory_protocols ();
 
 	ControlProtocol* instantiate (ControlProtocolInfo&);
@@ -77,11 +77,10 @@ struct ControlProtocolInfo {
 	ControlProtocolManager ();
 	static ControlProtocolManager* _instance;
 
-	Session* _session;
 	Glib::Mutex protocols_lock;
 	std::list<ControlProtocol*>    control_protocols;
 
-	void drop_session ();
+	void session_going_away ();
 
 	int control_protocol_discover (std::string path);
 	ControlProtocolDescriptor* get_descriptor (std::string path);
diff --git a/libs/ardour/ardour/crossfade.h b/libs/ardour/ardour/crossfade.h
index 5d8e0235fb..1a492b742b 100644
--- a/libs/ardour/ardour/crossfade.h
+++ b/libs/ardour/ardour/crossfade.h
@@ -24,7 +24,6 @@
 #include <algorithm>
 #include <boost/shared_ptr.hpp>
 
-#include <sigc++/signal.h>
 
 #include "pbd/undo.h"
 #include "pbd/statefuldestructible.h"
@@ -106,8 +105,8 @@ class Crossfade : public ARDOUR::AudioRegion
 
 	nframes_t overlap_length() const;
 
-	sigc::signal<void,boost::shared_ptr<Region> > Invalidated;
-	sigc::signal<void,Change>     StateChanged;
+	boost::signals2::signal<void(boost::shared_ptr<Region>)> Invalidated;
+	boost::signals2::signal<void(Change)>     StateChanged;
 
 	bool covers (nframes_t frame) const {
 		return _position <= frame && frame < _position + _length;
diff --git a/libs/ardour/ardour/delivery.h b/libs/ardour/ardour/delivery.h
index 1b1a217466..7a5931c5fb 100644
--- a/libs/ardour/ardour/delivery.h
+++ b/libs/ardour/ardour/delivery.h
@@ -20,6 +20,7 @@
 #define __ardour_delivery_h__
 
 #include <string>
+
 #include "ardour/types.h"
 #include "ardour/chan_count.h"
 #include "ardour/io_processor.h"
@@ -31,7 +32,8 @@ class IO;
 class MuteMaster;
 class Panner;
 
-class Delivery : public IOProcessor {
+class Delivery : public IOProcessor
+{
 public:
 	enum Role {
 		/* main outputs - delivers out-of-place to port buffers, and cannot be removed */
@@ -83,9 +85,9 @@ public:
 
 	BufferSet& output_buffers() { return *_output_buffers; }
 
-	sigc::signal<void> MuteChange;
+	boost::signals2::signal<void()> MuteChange;
 
-	static sigc::signal<void,nframes_t> CycleStart;
+	static boost::signals2::signal<void(nframes_t)> CycleStart;
 
 	XMLNode& state (bool full);
 	int set_state (const XMLNode&, int version);
@@ -118,10 +120,10 @@ public:
 	boost::shared_ptr<Panner> _panner;
 
 	static bool panners_legal;
-	static sigc::signal<int>            PannersLegal;
+	static boost::signals2::signal<int()>            PannersLegal;
 
 	int panners_became_legal ();
-	sigc::connection panner_legal_c;
+	boost::signals2::scoped_connection panner_legal_c;
 	void output_changed (IOChange, void*);
 
 	gain_t target_gain ();
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index 87fffb92f7..a9664daa32 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -27,8 +27,6 @@
 #include <cmath>
 #include <time.h>
 
-#include <sigc++/signal.h>
-
 #include <boost/utility.hpp>
 
 #include "evoral/types.hpp"
@@ -145,15 +143,15 @@ class Diskstream : public SessionObject, public boost::noncopyable
 	void move_processor_automation (boost::weak_ptr<Processor>,
 			std::list< Evoral::RangeMove<nframes_t> > const &);
 
-	sigc::signal<void>            RecordEnableChanged;
-	sigc::signal<void>            SpeedChanged;
-	sigc::signal<void>            ReverseChanged;
-	sigc::signal<void>            PlaylistChanged;
-	sigc::signal<void>            AlignmentStyleChanged;
-	sigc::signal<void,Location *> LoopSet;
+	boost::signals2::signal<void()>            RecordEnableChanged;
+	boost::signals2::signal<void()>            SpeedChanged;
+	boost::signals2::signal<void()>            ReverseChanged;
+	boost::signals2::signal<void()>            PlaylistChanged;
+	boost::signals2::signal<void()>            AlignmentStyleChanged;
+	boost::signals2::signal<void(Location *)> LoopSet;
 
-	static sigc::signal<void>     DiskOverrun;
-	static sigc::signal<void>     DiskUnderrun;
+	static boost::signals2::signal<void()>     DiskOverrun;
+	static boost::signals2::signal<void()>     DiskUnderrun;
 
   protected:
 	friend class Session;
@@ -306,11 +304,9 @@ class Diskstream : public SessionObject, public boost::noncopyable
 	nframes_t scrub_buffer_size;
 	nframes_t scrub_offset;
 
-	sigc::connection ports_created_c;
-	sigc::connection plmod_connection;
-	sigc::connection plgone_connection;
-	sigc::connection plregion_connection;
-	sigc::connection ic_connection;
+	PBD::ScopedConnectionList playlist_connections;
+
+	boost::signals2::scoped_connection ic_connection;
 
 	Flag _flags;
 
diff --git a/libs/ardour/ardour/element_importer.h b/libs/ardour/ardour/element_importer.h
index a203c5d37b..d728a4b989 100644
--- a/libs/ardour/ardour/element_importer.h
+++ b/libs/ardour/ardour/element_importer.h
@@ -24,8 +24,7 @@
 #include <string>
 #include <utility>
 
-#include <sigc++/signal.h>
-
+#include <boost/signals2.hpp>
 #include "ardour/types.h"
 
 class XMLTree;
@@ -73,10 +72,10 @@ class ElementImporter
 	bool broken () { return _broken; }
 
 	/// Signal that requests for anew name
-	static sigc::signal <std::pair<bool, std::string>, std::string, std::string> Rename;
+	static boost::signals2::signal <std::pair<bool, std::string> (std::string, std::string)> Rename;
 
 	/// Signal for ok/cancel prompting
-	static sigc::signal <bool, std::string> Prompt;
+	static boost::signals2::signal <bool(std::string)> Prompt;
 
   protected:
 
diff --git a/libs/ardour/ardour/export.h b/libs/ardour/ardour/export.h
index 78a0e9abb0..055168118d 100644
--- a/libs/ardour/ardour/export.h
+++ b/libs/ardour/ardour/export.h
@@ -24,7 +24,6 @@
 #include <vector>
 #include <string>
 
-#include <sigc++/signal.h>
 
 #include <sndfile.h>
 #include <samplerate.h>
@@ -39,7 +38,7 @@ namespace ARDOUR
 	typedef std::pair<Port *, uint32_t> PortChannelPair;
 	typedef std::map<uint32_t, std::vector<PortChannelPair> > ExportPortMap;
 
-	struct ExportSpecification : public SF_INFO, public sigc::trackable {
+	struct ExportSpecification : public SF_INFO, public PBD::ScopedConnectionList {
 
 		ExportSpecification();
 		~ExportSpecification ();
@@ -85,7 +84,7 @@ namespace ARDOUR
 		SRC_STATE*     src_state;
 		nframes_t      pos;
 
-		sigc::connection freewheel_connection;
+		boost::signals2::scoped_connection freewheel_connection;
 
 		/* shared between UI thread and audio thread */
 
diff --git a/libs/ardour/ardour/export_channel.h b/libs/ardour/ardour/export_channel.h
index fdb466a06e..4a2f74b775 100644
--- a/libs/ardour/ardour/export_channel.h
+++ b/libs/ardour/ardour/export_channel.h
@@ -21,13 +21,13 @@
 #ifndef __ardour_export_channel_h__
 #define __ardour_export_channel_h__
 
-#include "ardour/audioregion.h"
-#include "ardour/buffer_set.h"
-
 #include <set>
 
+#include <boost/signals2.hpp>
 #include <boost/shared_ptr.hpp>
-#include <sigc++/signal.h>
+
+#include "ardour/audioregion.h"
+#include "ardour/buffer_set.h"
 
 namespace ARDOUR {
 
@@ -89,7 +89,7 @@ class PortExportChannel : public ExportChannel
 };
 
 /// Handles RegionExportChannels and does actual reading from region
-class RegionExportChannelFactory : public sigc::trackable
+class RegionExportChannelFactory 
 {
   public:
 	enum Type {
@@ -106,7 +106,7 @@ class RegionExportChannelFactory : public sigc::trackable
 
   private:
 
-	int new_cycle_started () { buffers_up_to_date = false; return 0; }
+	int new_cycle_started (nframes_t) { buffers_up_to_date = false; return 0; }
 	void update_buffers (nframes_t frames);
 
 	AudioRegion const & region;
@@ -122,6 +122,8 @@ class RegionExportChannelFactory : public sigc::trackable
 
 	Sample * mixdown_buffer;
 	Sample * gain_buffer;
+
+	boost::signals2::scoped_connection export_connection;
 };
 
 /// Export channel that reads from region channel
diff --git a/libs/ardour/ardour/export_channel_configuration.h b/libs/ardour/ardour/export_channel_configuration.h
index 8ef9bba6dc..b8d7fa6bf1 100644
--- a/libs/ardour/ardour/export_channel_configuration.h
+++ b/libs/ardour/ardour/export_channel_configuration.h
@@ -24,7 +24,6 @@
 #include <list>
 
 #include <glibmm/ustring.h>
-#include <sigc++/signal.h>
 
 #include "ardour/export_channel.h"
 #include "ardour/export_status.h"
@@ -96,7 +95,7 @@ class ExportChannelConfiguration
 
 	/// Writes all files for this channel config @return true if a new thread was spawned
 	bool write_files (boost::shared_ptr<ExportProcessor> new_processor);
-	sigc::signal<void> FilesWritten;
+	boost::signals2::signal<void()> FilesWritten;
 
 	// Tells the handler the necessary information for it to handle tempfiles
 	void register_with_timespan (TimespanPtr timespan);
diff --git a/libs/ardour/ardour/export_format_base.h b/libs/ardour/ardour/export_format_base.h
index 7bc0125004..ceb11a2cc9 100644
--- a/libs/ardour/ardour/export_format_base.h
+++ b/libs/ardour/ardour/export_format_base.h
@@ -115,8 +115,8 @@ class ExportFormatBase {
 			: _selected (false), _compatible (true) { }
 		~SelectableCompatible () {}
 
-		sigc::signal<void, bool> SelectChanged;
-		sigc::signal<void, bool> CompatibleChanged;
+		boost::signals2::signal<void(bool)> SelectChanged;
+		boost::signals2::signal<void(bool)> CompatibleChanged;
 
 		bool selected () const { return _selected; }
 		bool compatible () const { return _compatible; }
diff --git a/libs/ardour/ardour/export_format_manager.h b/libs/ardour/ardour/export_format_manager.h
index 705b9dcf17..52463350fe 100644
--- a/libs/ardour/ardour/export_format_manager.h
+++ b/libs/ardour/ardour/export_format_manager.h
@@ -26,8 +26,8 @@
 
 #include <boost/shared_ptr.hpp>
 #include <boost/weak_ptr.hpp>
-#include <sigc++/signal.h>
-#include <sigc++/trackable.h>
+
+#include "pbd/scoped_connections.h"
 
 #include "ardour/export_formats.h"
 
@@ -39,7 +39,7 @@ class ExportFormatCompatibility;
 class ExportFormatSpecification;
 class AnyTime;
 
-class ExportFormatManager : public sigc::trackable
+class ExportFormatManager : public PBD::ScopedConnectionList
 {
   public:
 
@@ -92,7 +92,7 @@ class ExportFormatManager : public sigc::trackable
 
 	/* Signals */
 
-	sigc::signal<void, bool> CompleteChanged;
+	boost::signals2::signal<void(bool)> CompleteChanged;
 
 	/* Access to lists */
 
diff --git a/libs/ardour/ardour/export_formats.h b/libs/ardour/ardour/export_formats.h
index 3312e9abd6..3ef207097b 100644
--- a/libs/ardour/ardour/export_formats.h
+++ b/libs/ardour/ardour/export_formats.h
@@ -21,12 +21,14 @@
 #ifndef __ardour_export_formats_h__
 #define __ardour_export_formats_h__
 
-#include "ardour/export_format_base.h"
-#include "ardour/export_format_compatibility.h"
-
 #include <list>
 #include <boost/weak_ptr.hpp>
+
 #include "pbd/failed_constructor.h"
+#include "pbd/scoped_connections.h"
+
+#include "ardour/export_format_base.h"
+#include "ardour/export_format_compatibility.h"
 
 namespace ARDOUR
 {
@@ -84,7 +86,7 @@ class ExportFormat : public ExportFormatBase, public ExportFormatBase::Selectabl
 };
 
 /// Class to be inherited by export formats that have a selectable sample format
-class HasSampleFormat {
+class HasSampleFormat : public PBD::ScopedConnectionList {
   public:
 
 	class SampleFormatState : public ExportFormatBase::SelectableCompatible {
@@ -126,11 +128,11 @@ class HasSampleFormat {
 
 	/* Proxies for signals from sample formats and dither types */
 
-	sigc::signal<void, bool, WeakSampleFormatPtr> SampleFormatSelectChanged;
-	sigc::signal<void, bool, WeakSampleFormatPtr> SampleFormatCompatibleChanged;
+	boost::signals2::signal<void(bool, WeakSampleFormatPtr)> SampleFormatSelectChanged;
+	boost::signals2::signal<void(bool, WeakSampleFormatPtr)> SampleFormatCompatibleChanged;
 
-	sigc::signal<void, bool, WeakDitherTypePtr> DitherTypeSelectChanged;
-	sigc::signal<void, bool, WeakDitherTypePtr> DitherTypeCompatibleChanged;
+	boost::signals2::signal<void(bool, WeakDitherTypePtr)> DitherTypeSelectChanged;
+	boost::signals2::signal<void(bool, WeakDitherTypePtr)> DitherTypeCompatibleChanged;
 
 	static std::string get_sample_format_name (ExportFormatBase::SampleFormat format);
 
diff --git a/libs/ardour/ardour/export_handler.h b/libs/ardour/ardour/export_handler.h
index fad21ac780..ded6ed5b02 100644
--- a/libs/ardour/ardour/export_handler.h
+++ b/libs/ardour/ardour/export_handler.h
@@ -68,7 +68,7 @@ class ExportElementFactory
 	Session & session;
 };
 
-class ExportHandler : public ExportElementFactory, public sigc::trackable
+class ExportHandler : public ExportElementFactory
 {
   private:
 
@@ -118,8 +118,10 @@ class ExportHandler : public ExportElementFactory, public sigc::trackable
 
 	bool               realtime;
 
-	sigc::connection          files_written_connection;
+	boost::signals2::scoped_connection          files_written_connection;
+	boost::signals2::scoped_connection          export_read_finished_connection;
 	std::list<Glib::ustring> files_written;
+	void add_file (const Glib::ustring&);
 
 	/* CD Marker stuff */
 
@@ -175,7 +177,7 @@ class ExportHandler : public ExportElementFactory, public sigc::trackable
 	TimespanPtr          current_timespan;
 	ConfigMap::iterator  current_map_it;
 	TimespanBounds       timespan_bounds;
-	sigc::connection     channel_config_connection;
+	boost::signals2::scoped_connection     channel_config_connection;
 
 };
 
diff --git a/libs/ardour/ardour/export_multiplication.h b/libs/ardour/ardour/export_multiplication.h
index 4826a35668..aace72cc42 100644
--- a/libs/ardour/ardour/export_multiplication.h
+++ b/libs/ardour/ardour/export_multiplication.h
@@ -36,7 +36,7 @@
 		bool selected () const { return _selected; }
 		void select (bool value);
 
-		sigc::signal<void, bool> SelectChanged;
+		boost::signals2::signal<void(bool)> SelectChanged;
 
 	  protected:
 
@@ -151,7 +151,7 @@
 	void split_node (GraphNode * node, float position);
 	void remove_node (GraphNode * node);
 
-	sigc::signal<void> GraphChanged;
+	boost::signals2::signal<void()> GraphChanged;
 
   private:
 
diff --git a/libs/ardour/ardour/export_processor.h b/libs/ardour/ardour/export_processor.h
index c2cb5034c7..8e7918d7c5 100644
--- a/libs/ardour/ardour/export_processor.h
+++ b/libs/ardour/ardour/export_processor.h
@@ -80,7 +80,7 @@ class ExportProcessor
 
 	void write_files ();
 
-	static sigc::signal<void, Glib::ustring> WritingFile;
+	static boost::signals2::signal<void(const Glib::ustring&)> WritingFile;
 
   private:
 
diff --git a/libs/ardour/ardour/export_profile_manager.h b/libs/ardour/ardour/export_profile_manager.h
index 47acacd387..30bb3c5b91 100644
--- a/libs/ardour/ardour/export_profile_manager.h
+++ b/libs/ardour/ardour/export_profile_manager.h
@@ -28,7 +28,6 @@
 
 #include <boost/shared_ptr.hpp>
 #include <boost/weak_ptr.hpp>
-#include <sigc++/signal.h>
 #include <glibmm/ustring.h>
 
 #include "pbd/uuid.h"
@@ -207,7 +206,7 @@ class ExportProfileManager
 	void remove_format_profile (FormatPtr format);
 	FormatPtr get_new_format (FormatPtr original);
 
-	sigc::signal<void> FormatListChanged;
+	boost::signals2::signal<void()> FormatListChanged;
 
   private:
 
diff --git a/libs/ardour/ardour/export_status.h b/libs/ardour/ardour/export_status.h
index 3322ca639c..9fd3c84ecc 100644
--- a/libs/ardour/ardour/export_status.h
+++ b/libs/ardour/ardour/export_status.h
@@ -22,9 +22,9 @@
 #define __ardour_export_status_h__
 
 #include <list>
+#include <boost/signals2.hpp>
 
 #include <stdint.h>
-#include <sigc++/signal.h>
 
 namespace ARDOUR
 {
@@ -36,7 +36,7 @@ enum ExportStage {
 	export_Write
 };
 
-struct ExportStatus : public sigc::trackable {
+struct ExportStatus {
 
 	ExportStatus ();
 	void init ();
@@ -46,12 +46,12 @@ struct ExportStatus : public sigc::trackable {
 	volatile bool           stop;
 	volatile bool           running;
 
-	sigc::signal<void>      Aborting;
+	boost::signals2::signal<void()>      Aborting;
 	void abort (bool error_occurred = false);
 	bool aborted () const { return _aborted; }
 	bool errors () const { return _errors; }
 
-	sigc::signal<void>      Finished;
+	boost::signals2::signal<void()>      Finished;
 	void finish ();
 	bool finished () const { return _finished; }
 
diff --git a/libs/ardour/ardour/export_timespan.h b/libs/ardour/ardour/export_timespan.h
index 255d1e377d..461caf6dd8 100644
--- a/libs/ardour/ardour/export_timespan.h
+++ b/libs/ardour/ardour/export_timespan.h
@@ -36,7 +36,7 @@ namespace ARDOUR
 class ExportChannel;
 class ExportTempFile;
 
-class ExportTimespan : public sigc::trackable
+class ExportTimespan
 {
   private:
 	typedef boost::shared_ptr<ExportTempFile> TempFilePtr;
@@ -69,7 +69,7 @@ class ExportTimespan : public sigc::trackable
 	/// Reads data from each channel and writes to tempfile
 	int process (nframes_t frames);
 
-	sigc::connection  process_connection;
+	boost::signals2::scoped_connection  process_connection;
 
 	void set_range (nframes_t start, nframes_t end);
 	nframes_t get_length () const { return end_frame - start_frame; }
diff --git a/libs/ardour/ardour/import_status.h b/libs/ardour/ardour/import_status.h
index 25a14f3fae..e6207c6ee8 100644
--- a/libs/ardour/ardour/import_status.h
+++ b/libs/ardour/ardour/import_status.h
@@ -24,7 +24,6 @@
 #include <vector>
 
 #include <stdint.h>
-#include <sigc++/signal.h>
 
 #include "ardour/types.h"
 
diff --git a/libs/ardour/ardour/internal_return.h b/libs/ardour/ardour/internal_return.h
index 205559fe4e..498c9f3605 100644
--- a/libs/ardour/ardour/internal_return.h
+++ b/libs/ardour/ardour/internal_return.h
@@ -20,7 +20,6 @@
 #ifndef __ardour_internal_return_h__
 #define __ardour_internal_return_h__
 
-#include <sigc++/signal.h>
 
 #include "ardour/ardour.h"
 #include "ardour/return.h"
@@ -48,7 +47,7 @@ class InternalReturn : public Return
 	BufferSet* get_buffers();
 	void release_buffers();
 
-	static sigc::signal<void,nframes_t> CycleStart;
+	static boost::signals2::signal<void(nframes_t)> CycleStart;
 
   private:
 	BufferSet buffers;
diff --git a/libs/ardour/ardour/internal_send.h b/libs/ardour/ardour/internal_send.h
index 12279b166e..7573efd685 100644
--- a/libs/ardour/ardour/internal_send.h
+++ b/libs/ardour/ardour/internal_send.h
@@ -53,7 +53,7 @@ class InternalSend : public Send
 	BufferSet* target;
 	boost::shared_ptr<Route> _send_to;
 	PBD::ID _send_to_id;
-	sigc::connection connect_c;
+	boost::signals2::scoped_connection connect_c;
 
 	void send_to_going_away ();
 	void send_to_name_changed ();
diff --git a/libs/ardour/ardour/io.h b/libs/ardour/ardour/io.h
index da0b88e5fe..eeb7ed64f0 100644
--- a/libs/ardour/ardour/io.h
+++ b/libs/ardour/ardour/io.h
@@ -23,7 +23,6 @@
 #include <string>
 #include <vector>
 #include <cmath>
-#include <sigc++/signal.h>
 #include <jack/jack.h>
 
 #include <glibmm/thread.h>
@@ -133,7 +132,7 @@ class IO : public SessionObject, public Latent
 
 	const ChanCount& n_ports ()  const { return _ports.count(); }
 
-	sigc::signal<void,IOChange,void*> changed;
+	boost::signals2::signal<void(IOChange,void*)> changed;
 
 	virtual XMLNode& state (bool full);
 	XMLNode& get_state (void);
@@ -145,7 +144,7 @@ class IO : public SessionObject, public Latent
 	static int  disable_ports (void);
 	static int  enable_ports (void);
 
-	static sigc::signal<void,ChanCount> PortCountChanged; // emitted when the number of ports changes
+	static boost::signals2::signal<void(ChanCount)> PortCountChanged; // emitted when the number of ports changes
 
 	static std::string name_from_state (const XMLNode&);
 	static void set_name_in_state (XMLNode&, const std::string&);
@@ -153,7 +152,7 @@ class IO : public SessionObject, public Latent
 	/* we have to defer/order port connection. this is how we do it.
 	*/
 
-	static sigc::signal<int> ConnectingLegal;
+	static boost::signals2::signal<int()> ConnectingLegal;
 	static bool              connecting_legal;
 
 	XMLNode *pending_state_node;
@@ -180,20 +179,18 @@ class IO : public SessionObject, public Latent
 	bool     _active;
 
   private:
-
 	int connecting_became_legal ();
-	sigc::connection connection_legal_c;
+	boost::signals2::scoped_connection connection_legal_c;
 
 	boost::shared_ptr<Bundle> _bundle; ///< a bundle representing our ports
 
 	struct UserBundleInfo {
-		UserBundleInfo (IO*, boost::shared_ptr<UserBundle> b);
-
-		boost::shared_ptr<UserBundle> bundle;
-		sigc::connection changed;
+	    UserBundleInfo (IO*, boost::shared_ptr<UserBundle> b);
+	    boost::shared_ptr<UserBundle> bundle;
+	    boost::signals2::scoped_connection changed;
 	};
-
-	std::vector<UserBundleInfo> _bundles_connected; ///< user bundles connected to our ports
+	
+	std::vector<UserBundleInfo*> _bundles_connected; ///< user bundles connected to our ports
 
 	static int parse_io_string (const std::string&, std::vector<std::string>& chns);
 	static int parse_gain_string (const std::string&, std::vector<std::string>& chns);
@@ -201,7 +198,7 @@ class IO : public SessionObject, public Latent
 	int ensure_ports (ChanCount, bool clear, bool lockit, void *src);
 
 	void check_bundles_connected ();
-	void check_bundles (std::vector<UserBundleInfo>&, const PortSet&);
+	void check_bundles (std::vector<UserBundleInfo*>&, const PortSet&);
 
 	void bundle_changed (Bundle::Change);
 
diff --git a/libs/ardour/ardour/io_processor.h b/libs/ardour/ardour/io_processor.h
index 0d564bb00c..e4a42a80e2 100644
--- a/libs/ardour/ardour/io_processor.h
+++ b/libs/ardour/ardour/io_processor.h
@@ -22,7 +22,6 @@
 
 #include <string>
 #include <boost/shared_ptr.hpp>
-#include <sigc++/signal.h>
 
 #include <glibmm/thread.h>
 
@@ -68,8 +67,8 @@ class IOProcessor : public Processor
 
 	virtual bool feeds (boost::shared_ptr<Route> other) const;
 
-	sigc::signal<void,IOProcessor*,bool>     AutomationPlaybackChanged;
-	sigc::signal<void,IOProcessor*,uint32_t> AutomationChanged;
+	boost::signals2::signal<void(IOProcessor*,bool)>     AutomationPlaybackChanged;
+	boost::signals2::signal<void(IOProcessor*,uint32_t)> AutomationChanged;
 
 	XMLNode& state (bool full_state);
 	int set_state (const XMLNode&, int version);
diff --git a/libs/ardour/ardour/jack_port.h b/libs/ardour/ardour/jack_port.h
index 3101ce9523..0bb0752d55 100644
--- a/libs/ardour/ardour/jack_port.h
+++ b/libs/ardour/ardour/jack_port.h
@@ -20,7 +20,6 @@
 #ifndef __ardour_jack_port_h__
 #define __ardour_jack_port_h__
 
-#include <sigc++/signal.h>
 #include "pbd/failed_constructor.h"
 #include "ardour/port.h"
 #include <jack/jack.h>
diff --git a/libs/ardour/ardour/ladspa_plugin.h b/libs/ardour/ardour/ladspa_plugin.h
index 656c13afae..00f00c99b6 100644
--- a/libs/ardour/ardour/ladspa_plugin.h
+++ b/libs/ardour/ardour/ladspa_plugin.h
@@ -25,7 +25,6 @@
 #include <string>
 #include <dlfcn.h>
 
-#include <sigc++/signal.h>
 
 #include "pbd/stateful.h"
 
diff --git a/libs/ardour/ardour/location.h b/libs/ardour/ardour/location.h
index 149a559d85..b50a645a93 100644
--- a/libs/ardour/ardour/location.h
+++ b/libs/ardour/ardour/location.h
@@ -26,7 +26,6 @@
 #include <map>
 
 #include <sys/types.h>
-#include <sigc++/signal.h>
 
 #include <glibmm/thread.h>
 
@@ -109,15 +108,15 @@ class Location : public PBD::StatefulDestructible
 	bool is_range_marker() const { return _flags & IsRangeMarker; }
 	bool matches (Flags f) const { return _flags & f; }
 
-	sigc::signal<void,Location*> name_changed;
-	sigc::signal<void,Location*> end_changed;
-	sigc::signal<void,Location*> start_changed;
+	boost::signals2::signal<void(Location*)> name_changed;
+	boost::signals2::signal<void(Location*)> end_changed;
+	boost::signals2::signal<void(Location*)> start_changed;
 
-	sigc::signal<void,Location*,void*> FlagsChanged;
+	boost::signals2::signal<void(Location*,void*)> FlagsChanged;
 
 	/* this is sent only when both start&end change at the same time */
 
-	sigc::signal<void,Location*> changed;
+	boost::signals2::signal<void(Location*)> changed;
 
 	/* CD Track / CD-Text info */
 
@@ -176,11 +175,11 @@ class Locations : public PBD::StatefulDestructible
 
 	void find_all_between (nframes64_t start, nframes64_t, LocationList&, Location::Flags);
 
-	sigc::signal<void,Location*> current_changed;
-	sigc::signal<void>           changed;
-	sigc::signal<void,Location*> added;
-	sigc::signal<void,Location*> removed;
-	sigc::signal<void,Change>    StateChanged;
+	boost::signals2::signal<void(Location*)> current_changed;
+	boost::signals2::signal<void()>           changed;
+	boost::signals2::signal<void(Location*)> added;
+	boost::signals2::signal<void(Location*)> removed;
+	boost::signals2::signal<void(Change)>    StateChanged;
 
 	template<class T> void apply (T& obj, void (T::*method)(LocationList&)) {
 		Glib::Mutex::Lock lm (lock);
diff --git a/libs/ardour/ardour/lv2_plugin.h b/libs/ardour/ardour/lv2_plugin.h
index 9705459ee1..157d9144b8 100644
--- a/libs/ardour/ardour/lv2_plugin.h
+++ b/libs/ardour/ardour/lv2_plugin.h
@@ -26,7 +26,6 @@
 #include <string>
 #include <dlfcn.h>
 
-#include <sigc++/signal.h>
 
 #include "pbd/stateful.h"
 
diff --git a/libs/ardour/ardour/meter.h b/libs/ardour/ardour/meter.h
index ae0a1672db..1f5e3307d6 100644
--- a/libs/ardour/ardour/meter.h
+++ b/libs/ardour/ardour/meter.h
@@ -20,7 +20,6 @@
 #define __ardour_meter_h__
 
 #include <vector>
-#include <sigc++/slot.h>
 #include "ardour/types.h"
 #include "ardour/processor.h"
 #include "pbd/fastlog.h"
@@ -34,10 +33,10 @@ class Session;
 class Metering {
   public:
 	static void               update_meters ();
-	static sigc::signal<void> Meter;
+	static boost::signals2::signal<void()> Meter;
 
-	static sigc::connection   connect (sigc::slot<void> the_slot);
-	static void               disconnect (sigc::connection& c);
+	static boost::signals2::connection connect (boost::function<void()>);
+	static void                        disconnect (boost::signals2::connection& c);
 
   private:
 	/* this object is not meant to be instantiated */
diff --git a/libs/ardour/ardour/midi_diskstream.h b/libs/ardour/ardour/midi_diskstream.h
index 930d37330a..72667ca662 100644
--- a/libs/ardour/ardour/midi_diskstream.h
+++ b/libs/ardour/ardour/midi_diskstream.h
@@ -21,7 +21,6 @@
 #ifndef __ardour_midi_diskstream_h__
 #define __ardour_midi_diskstream_h__
 
-#include <sigc++/signal.h>
 
 #include <cmath>
 #include <cassert>
diff --git a/libs/ardour/ardour/midi_model.h b/libs/ardour/ardour/midi_model.h
index b099f575a1..9961b51528 100644
--- a/libs/ardour/ardour/midi_model.h
+++ b/libs/ardour/ardour/midi_model.h
@@ -158,7 +158,7 @@ public:
 	XMLNode& get_state();
 	int set_state(const XMLNode&) { return 0; }
 
-	sigc::signal<void> ContentsChanged;
+	boost::signals2::signal<void()> ContentsChanged;
 
 	const MidiSource* midi_source() const { return _midi_source; }
 	void set_midi_source(MidiSource* source) { _midi_source = source; }
diff --git a/libs/ardour/ardour/midi_patch_manager.h b/libs/ardour/ardour/midi_patch_manager.h
index a48c9ddfe7..8c4ff43d5c 100644
--- a/libs/ardour/ardour/midi_patch_manager.h
+++ b/libs/ardour/ardour/midi_patch_manager.h
@@ -22,6 +22,8 @@
 #define MIDI_PATCH_MANAGER_H_
 
 #include "midi++/midnam_patch.h"
+#include "pbd/scoped_connections.h"
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 	class Session;
@@ -33,7 +35,7 @@ namespace MIDI
 namespace Name
 {
 
-class MidiPatchManager
+class MidiPatchManager : public PBD::ScopedConnectionList, public ARDOUR::SessionHandlePtr
 {
 	/// Singleton
 private:
@@ -55,7 +57,7 @@ public:
 		return *_manager;
 	}
 
-	void set_session (ARDOUR::Session&);
+	void set_session (ARDOUR::Session*);
 
 	boost::shared_ptr<MIDINameDocument> document_by_model(std::string model_name)
 		{ return _documents[model_name]; }
@@ -76,7 +78,6 @@ public:
 		}
 	}
 
-
 	boost::shared_ptr<Patch> find_patch(
 			std::string model,
 			std::string custom_device_mode,
@@ -133,10 +134,9 @@ public:
 	const MasterDeviceNames::Models& all_models() const { return _all_models; }
 
 private:
-	void drop_session();
+	void session_going_away();
 	void refresh();
 
-	ARDOUR::Session*                        _session;
 	MidiNameDocuments                       _documents;
 	MIDINameDocument::MasterDeviceNamesList _master_devices_by_model;
 	MasterDeviceNames::Models               _all_models;
@@ -145,4 +145,5 @@ private:
 } // namespace Name
 
 } // namespace MIDI
+
 #endif /* MIDI_PATCH_MANAGER_H_ */
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index dfbd5ea6a2..74448991d9 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -22,7 +22,6 @@
 
 #include <string>
 #include <time.h>
-#include <sigc++/signal.h>
 #include <glibmm/thread.h>
 #include "pbd/stateful.h"
 #include "pbd/xml++.h"
@@ -87,10 +86,10 @@ class MidiSource : virtual public Source
 	uint32_t read_data_count()  const { return _read_data_count; }
 	uint32_t write_data_count() const { return _write_data_count; }
 
-	static sigc::signal<void,MidiSource*> MidiSourceCreated;
+	static boost::signals2::signal<void(MidiSource*)> MidiSourceCreated;
 
 	// Signal a range of recorded data is available for reading from model()
-	mutable sigc::signal<void,sframes_t,nframes_t> ViewDataRangeReady;
+	mutable boost::signals2::signal<void(sframes_t,nframes_t)> ViewDataRangeReady;
 
 	XMLNode& get_state ();
 	int set_state (const XMLNode&, int version);
diff --git a/libs/ardour/ardour/midi_ui.h b/libs/ardour/ardour/midi_ui.h
index 2daec06774..0ecf1b0589 100644
--- a/libs/ardour/ardour/midi_ui.h
+++ b/libs/ardour/ardour/midi_ui.h
@@ -2,6 +2,7 @@
 #define __libardour_midi_ui_h__
 
 #include <list>
+#include <boost/signals2.hpp>
 #include "pbd/abstract_ui.h"
 
 namespace MIDI { 
@@ -41,7 +42,8 @@ class MidiControlUI : public AbstractUI<MidiUIRequest>
 	typedef std::list<GSource*> PortSources;
 	PortSources port_sources;
 	ARDOUR::Session& _session;
-	
+	boost::signals2::scoped_connection rebind_connection;
+
 	bool midi_input_handler (Glib::IOCondition, MIDI::Port*);
 	void reset_ports ();
 	void clear_ports ();
diff --git a/libs/ardour/ardour/mute_master.h b/libs/ardour/ardour/mute_master.h
index ef65e69aba..a76775c710 100644
--- a/libs/ardour/ardour/mute_master.h
+++ b/libs/ardour/ardour/mute_master.h
@@ -64,7 +64,7 @@ class MuteMaster : public AutomationControl
 	void set_value (float); /* note: float is used as a bitfield of MutePoints */
 	float get_value () const;
 
-	sigc::signal<void> MutePointChanged;
+	boost::signals2::signal<void()> MutePointChanged;
 
 	XMLNode& get_state();
 	int set_state(const XMLNode&, int version);
diff --git a/libs/ardour/ardour/named_selection.h b/libs/ardour/ardour/named_selection.h
index d41f104e1a..0c930d5b72 100644
--- a/libs/ardour/ardour/named_selection.h
+++ b/libs/ardour/ardour/named_selection.h
@@ -46,7 +46,7 @@ struct NamedSelection : public PBD::Stateful
 
     int set_state (const XMLNode&, int version);
 
-    static sigc::signal<void,NamedSelection*> NamedSelectionCreated;
+    static boost::signals2::signal<void(NamedSelection*)> NamedSelectionCreated;
 };
 
 }/* namespace ARDOUR */
diff --git a/libs/ardour/ardour/panner.h b/libs/ardour/ardour/panner.h
index 7ea37e9974..bf5a04c745 100644
--- a/libs/ardour/ardour/panner.h
+++ b/libs/ardour/ardour/panner.h
@@ -25,7 +25,6 @@
 #include <vector>
 #include <string>
 #include <iostream>
-#include <sigc++/signal.h>
 
 #include "pbd/stateful.h"
 #include "pbd/controllable.h"
@@ -41,7 +40,7 @@ class Panner;
 class BufferSet;
 class AudioBuffer;
 
-class StreamPanner : public sigc::trackable, public PBD::Stateful
+class StreamPanner : public PBD::Stateful
 {
   public:
 	StreamPanner (Panner& p, Evoral::Parameter param);
@@ -82,8 +81,8 @@ class StreamPanner : public sigc::trackable, public PBD::Stateful
 
 	boost::shared_ptr<AutomationControl> pan_control()  { return _control; }
 
-	sigc::signal<void> Changed;      /* for position */
-	sigc::signal<void> StateChanged; /* for mute */
+	boost::signals2::signal<void()> Changed;      /* for position */
+	boost::signals2::signal<void()> StateChanged; /* for mute */
 
 	int set_state (const XMLNode&, int version);
 	virtual XMLNode& state (bool full_state) = 0;
@@ -271,9 +270,9 @@ public:
 	StreamPanner &streampanner( uint32_t n ) const { assert( n < _streampanners.size() ); return *_streampanners[n]; }
 	uint32_t npanners() const { return _streampanners.size(); }
 
-	sigc::signal<void> Changed;
-	sigc::signal<void> LinkStateChanged;
-	sigc::signal<void> StateChanged; /* for bypass */
+	boost::signals2::signal<void()> Changed;
+	boost::signals2::signal<void()> LinkStateChanged;
+	boost::signals2::signal<void()> StateChanged; /* for bypass */
 
 	/* only StreamPanner should call these */
 
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index 3ed32f0984..9c089c2f05 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -32,7 +32,6 @@
 
 #include <glib.h>
 
-#include <sigc++/signal.h>
 
 #include "pbd/undo.h"
 #include "pbd/stateful.h"
@@ -51,9 +50,9 @@ namespace ARDOUR  {
 class Session;
 class Region;
 
-class Playlist : public SessionObject,
-                 public boost::noncopyable,
-                 public boost::enable_shared_from_this<Playlist> {
+class Playlist : public SessionObject
+	       , public boost::noncopyable
+	       , public boost::enable_shared_from_this<Playlist> {
   public:
 	typedef std::list<boost::shared_ptr<Region> >    RegionList;
 
@@ -125,19 +124,19 @@ class Playlist : public SessionObject,
 
 	nframes64_t find_next_transient (nframes64_t position, int dir);
 
-	void foreach_region (sigc::slot<void, boost::shared_ptr<Region> >);
+	void foreach_region (boost::function<void (boost::shared_ptr<Region>)>);
 
 	XMLNode& get_state ();
 	int set_state (const XMLNode&, int version);
 	XMLNode& get_template ();
 
-	sigc::signal<void,bool> InUse;
-	sigc::signal<void>      Modified;
-	sigc::signal<void, boost::weak_ptr<Region> > RegionAdded;
-	sigc::signal<void, boost::weak_ptr<Region> > RegionRemoved;
-	sigc::signal<void>      NameChanged;
-	sigc::signal<void>      LengthChanged;
-	sigc::signal<void, std::list< Evoral::RangeMove<nframes_t> > const &> RangesMoved;
+	boost::signals2::signal<void(bool)> InUse;
+	boost::signals2::signal<void()>      Modified;
+	boost::signals2::signal<void(boost::weak_ptr<Region>)> RegionAdded;
+	boost::signals2::signal<void(boost::weak_ptr<Region>)> RegionRemoved;
+	boost::signals2::signal<void()>      NameChanged;
+	boost::signals2::signal<void()>      LengthChanged;
+	boost::signals2::signal<void(std::list< Evoral::RangeMove<nframes_t> > const &)> RangesMoved;
 
 	static std::string bump_name (std::string old_name, Session&);
 
@@ -195,7 +194,7 @@ class Playlist : public SessionObject,
 
 	RegionList       regions;  /* the current list of regions in the playlist */
 	std::set<boost::shared_ptr<Region> > all_regions; /* all regions ever added to this playlist */
-	std::list<sigc::connection> region_state_changed_connections;
+	PBD::ScopedConnectionList region_state_changed_connections;
 	DataType        _type;
 	mutable gint    block_notifications;
 	mutable gint    ignore_state_changes;
diff --git a/libs/ardour/ardour/playlist_factory.h b/libs/ardour/ardour/playlist_factory.h
index 02bd68ae7a..4c3680ae8e 100644
--- a/libs/ardour/ardour/playlist_factory.h
+++ b/libs/ardour/ardour/playlist_factory.h
@@ -31,7 +31,7 @@ class Session;
 class PlaylistFactory {
 
   public:
-	static sigc::signal<void,boost::shared_ptr<Playlist>, bool> PlaylistCreated;
+	static boost::signals2::signal<void(boost::shared_ptr<Playlist>, bool)> PlaylistCreated;
 
 	static boost::shared_ptr<Playlist> create (Session&, const XMLNode&, bool hidden = false, bool unused = false);
 	static boost::shared_ptr<Playlist> create (DataType type, Session&, std::string name, bool hidden = false);
diff --git a/libs/ardour/ardour/plugin.h b/libs/ardour/ardour/plugin.h
index 5a86b6e005..ea8f95d8f5 100644
--- a/libs/ardour/ardour/plugin.h
+++ b/libs/ardour/ardour/plugin.h
@@ -21,7 +21,6 @@
 #define __ardour_plugin_h__
 
 #include <boost/shared_ptr.hpp>
-#include <sigc++/signal.h>
 #include <glibmm/ustring.h>
 
 #include "pbd/statefuldestructible.h"
@@ -144,7 +143,7 @@ class Plugin : public PBD::StatefulDestructible, public Latent
 
 	virtual bool has_editor() const = 0;
 
-	sigc::signal<void,uint32_t,float> ParameterChanged;
+	boost::signals2::signal<void(uint32_t,float)> ParameterChanged;
 
 	/* NOTE: this block of virtual methods looks like the interface
 	   to a Processor, but Plugin does not inherit from Processor.
diff --git a/libs/ardour/ardour/plugin_insert.h b/libs/ardour/ardour/plugin_insert.h
index 593db1ff0d..6be8f1dda6 100644
--- a/libs/ardour/ardour/plugin_insert.h
+++ b/libs/ardour/ardour/plugin_insert.h
@@ -25,7 +25,6 @@
 
 #include <boost/weak_ptr.hpp>
 
-#include <sigc++/signal.h>
 #include "ardour/ardour.h"
 #include "ardour/types.h"
 #include "ardour/processor.h"
@@ -107,7 +106,7 @@ class PluginInsert : public Processor
 
 	void collect_signal_for_analysis(nframes_t nframes);
 
-	sigc::signal<void, BufferSet*, BufferSet*> AnalysisDataGathered;
+	boost::signals2::signal<void(BufferSet*, BufferSet*)> AnalysisDataGathered;
 
   private:
 	/* disallow copy construction */
diff --git a/libs/ardour/ardour/plugin_manager.h b/libs/ardour/ardour/plugin_manager.h
index 0a056b574a..44c529835e 100644
--- a/libs/ardour/ardour/plugin_manager.h
+++ b/libs/ardour/ardour/plugin_manager.h
@@ -70,7 +70,7 @@ class PluginManager : public boost::noncopyable {
 	PluginStatusType get_status (const PluginInfoPtr&);
 
 	/** plugins were added to or removed from one of the PluginInfoLists */
-	sigc::signal<void> PluginListChanged;
+	boost::signals2::signal<void()> PluginListChanged;
 
   private:
 	struct PluginStatus {
diff --git a/libs/ardour/ardour/port.h b/libs/ardour/ardour/port.h
index 2597fa9601..be4df6bd02 100644
--- a/libs/ardour/ardour/port.h
+++ b/libs/ardour/ardour/port.h
@@ -25,7 +25,8 @@
 #include <vector>
 #include <jack/jack.h>
 #include <boost/utility.hpp>
-#include <sigc++/trackable.h>
+#include <boost/signals2.hpp>
+
 #include "ardour/data_type.h"
 #include "ardour/types.h"
 
@@ -34,7 +35,7 @@ namespace ARDOUR {
 class AudioEngine;
 class Buffer;
 
-class Port : public sigc::trackable, public boost::noncopyable
+class Port : public boost::noncopyable
 {
 public:
 	enum Flags {
@@ -117,7 +118,7 @@ public:
 
 	static void set_engine (AudioEngine *);
 
-	sigc::signal<void, bool> MonitorInputChanged;
+	boost::signals2::signal<void(bool)> MonitorInputChanged;
 
 protected:
 
diff --git a/libs/ardour/ardour/port_insert.h b/libs/ardour/ardour/port_insert.h
index 97f930df6e..5e50b4775e 100644
--- a/libs/ardour/ardour/port_insert.h
+++ b/libs/ardour/ardour/port_insert.h
@@ -24,7 +24,6 @@
 #include <string>
 #include <exception>
 
-#include <sigc++/signal.h>
 #include "ardour/ardour.h"
 #include "ardour/io_processor.h"
 #include "ardour/types.h"
diff --git a/libs/ardour/ardour/processor.h b/libs/ardour/ardour/processor.h
index c57eb4354c..5962e8f44e 100644
--- a/libs/ardour/ardour/processor.h
+++ b/libs/ardour/ardour/processor.h
@@ -26,7 +26,6 @@
 
 #include "pbd/statefuldestructible.h"
 
-#include <sigc++/signal.h>
 
 #include "ardour/ardour.h"
 #include "ardour/automatable_controls.h"
@@ -99,10 +98,10 @@ class Processor : public SessionObject, public AutomatableControls, public Laten
 	void *get_gui () const { return _gui; }
 	void  set_gui (void *p) { _gui = p; }
 
-	static sigc::signal<void,Processor*> ProcessorCreated;
+	static boost::signals2::signal<void(Processor*)> ProcessorCreated;
 
-	sigc::signal<void>                     ActiveChanged;
-	sigc::signal<void,ChanCount,ChanCount> ConfigurationChanged;
+	boost::signals2::signal<void()>                     ActiveChanged;
+	boost::signals2::signal<void(ChanCount,ChanCount)> ConfigurationChanged;
 
 protected:
 	int       _pending_active;
diff --git a/libs/ardour/ardour/region.h b/libs/ardour/ardour/region.h
index 7bae98e573..a276fb19ee 100644
--- a/libs/ardour/ardour/region.h
+++ b/libs/ardour/ardour/region.h
@@ -26,6 +26,7 @@
 #include <boost/utility.hpp>
 
 #include "pbd/undo.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/ardour.h"
 #include "ardour/data_type.h"
@@ -95,8 +96,8 @@ class Region
 	static Change LayerChanged;
 	static Change HiddenChanged;
 
-	sigc::signal<void,Change> StateChanged;
-	static sigc::signal<void,boost::shared_ptr<ARDOUR::Region> > RegionPropertyChanged;
+	boost::signals2::signal<void(Change)> StateChanged;
+	static boost::signals2::signal<void(boost::shared_ptr<ARDOUR::Region>)> RegionPropertyChanged;
 	void unlock_property_changes () { _flags = Flag (_flags & ~DoNotSendPropertyChanges); }
 	void block_property_changes () { _flags = Flag (_flags | DoNotSendPropertyChanges); }
 
@@ -218,7 +219,7 @@ class Region
 	boost::shared_ptr<ARDOUR::Playlist> playlist() const { return _playlist.lock(); }
 	virtual void set_playlist (boost::weak_ptr<ARDOUR::Playlist>);
 
-	void source_deleted (boost::shared_ptr<Source>);
+	void source_deleted (boost::weak_ptr<Source>);
 
 	boost::shared_ptr<Source> source (uint32_t n=0) const { return _sources[ (n < _sources.size()) ? n : 0 ]; }
 	uint32_t                  n_channels()          const { return _sources.size(); }
diff --git a/libs/ardour/ardour/region_factory.h b/libs/ardour/ardour/region_factory.h
index e702a2433f..51858e4926 100644
--- a/libs/ardour/ardour/region_factory.h
+++ b/libs/ardour/ardour/region_factory.h
@@ -40,7 +40,7 @@ class RegionFactory {
 	   itself, to permit dynamic_cast<> to be used to
 	   infer the type of Region.
 	*/
-	static sigc::signal<void,boost::shared_ptr<Region> > CheckNewRegion;
+	static boost::signals2::signal<void(boost::shared_ptr<Region>)>  CheckNewRegion;
 
 	static boost::shared_ptr<Region> create (boost::shared_ptr<const Region>);
 
diff --git a/libs/ardour/ardour/return.h b/libs/ardour/ardour/return.h
index a3d3859899..f663c109a5 100644
--- a/libs/ardour/ardour/return.h
+++ b/libs/ardour/ardour/return.h
@@ -21,7 +21,6 @@
 #ifndef __ardour_return_h__
 #define __ardour_return_h__
 
-#include <sigc++/signal.h>
 #include <string>
 
 
diff --git a/libs/ardour/ardour/route.h b/libs/ardour/ardour/route.h
index 92a3c8c6b8..dd6173e963 100644
--- a/libs/ardour/ardour/route.h
+++ b/libs/ardour/ardour/route.h
@@ -163,7 +163,7 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 
 	void flush_processors ();
 
-	void foreach_processor (sigc::slot<void, boost::weak_ptr<Processor> > method) {
+	void foreach_processor (boost::function<void(boost::weak_ptr<Processor>)> method) {
 		Glib::RWLock::ReaderLock lm (_processor_lock);
 		for (ProcessorList::iterator i = _processors.begin(); i != _processors.end(); ++i) {
 			method (boost::weak_ptr<Processor> (*i));
@@ -227,28 +227,28 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 	void set_user_latency (nframes_t);
 	nframes_t initial_delay() const { return _initial_delay; }
 
-	sigc::signal<void>       active_changed;
-	sigc::signal<void>       phase_invert_changed;
-	sigc::signal<void>       denormal_protection_changed;
-	sigc::signal<void,void*> listen_changed;
-	sigc::signal<void,void*> solo_changed;
-	sigc::signal<void,void*> solo_safe_changed;
-	sigc::signal<void,void*> solo_isolated_changed;
-	sigc::signal<void,void*> comment_changed;
-	sigc::signal<void,void*> mute_changed;
-	sigc::signal<void>       mute_points_changed;
+	boost::signals2::signal<void()>       active_changed;
+	boost::signals2::signal<void()>       phase_invert_changed;
+	boost::signals2::signal<void()>       denormal_protection_changed;
+	boost::signals2::signal<void(void*)> listen_changed;
+	boost::signals2::signal<void(void*)> solo_changed;
+	boost::signals2::signal<void(void*)> solo_safe_changed;
+	boost::signals2::signal<void(void*)> solo_isolated_changed;
+	boost::signals2::signal<void(void*)> comment_changed;
+	boost::signals2::signal<void(void*)> mute_changed;
+	boost::signals2::signal<void()>       mute_points_changed;
 
 	/** the processors have changed; the parameter indicates what changed */
-	sigc::signal<void, RouteProcessorChange> processors_changed;
-	sigc::signal<void,void*> record_enable_changed;
+	boost::signals2::signal<void(RouteProcessorChange)> processors_changed;
+	boost::signals2::signal<void(void*)> record_enable_changed;
 	/** the metering point has changed */
-	sigc::signal<void,void*> meter_change; 
-	sigc::signal<void>       signal_latency_changed;
-	sigc::signal<void>       initial_delay_changed;
+	boost::signals2::signal<void(void*)> meter_change; 
+	boost::signals2::signal<void()>       signal_latency_changed;
+	boost::signals2::signal<void()>       initial_delay_changed;
 
 	/* gui's call this for their own purposes. */
 
-	sigc::signal<void,std::string,void*> gui_changed;
+	boost::signals2::signal<void(std::string,void*)> gui_changed;
 
 	/* stateful */
 
@@ -261,7 +261,7 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 
 	int save_as_template (const std::string& path, const std::string& name);
 
-	sigc::signal<void,void*> SelectedChanged;
+	boost::signals2::signal<void(void*)> SelectedChanged;
 
 	int listen_via (boost::shared_ptr<Route>, Placement p, bool active, bool aux);
 	void drop_listen (boost::shared_ptr<Route>);
@@ -306,10 +306,10 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 
 	void set_remote_control_id (uint32_t id);
 	uint32_t remote_control_id () const;
-	sigc::signal<void> RemoteControlIDChanged;
+	boost::signals2::signal<void()> RemoteControlIDChanged;
 
 	void sync_order_keys (std::string const &);
-	static sigc::signal<void, std::string const &> SyncOrderKeys;
+	static boost::signals2::signal<void(std::string const &)> SyncOrderKeys;
 
   protected:
 	friend class Session;
@@ -379,8 +379,6 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 
 	void silence (nframes_t nframes);
 
-	sigc::connection input_signal_connection;
-
 	ChanCount processor_max_streams;
 	uint32_t _remote_control_id;
 
@@ -391,7 +389,6 @@ class Route : public SessionObject, public AutomatableControls, public RouteGrou
 
 	boost::shared_ptr<Amp>       _amp;
 	boost::shared_ptr<PeakMeter> _meter;
-	sigc::connection _meter_connection;
 
   private:
 	void init ();
diff --git a/libs/ardour/ardour/route_group.h b/libs/ardour/ardour/route_group.h
index bec9a7e8a9..fe4079050d 100644
--- a/libs/ardour/ardour/route_group.h
+++ b/libs/ardour/ardour/route_group.h
@@ -24,9 +24,11 @@
 #include <set>
 #include <string>
 #include <stdint.h>
-#include <sigc++/signal.h>
+#include <boost/signals2.hpp>
 
 #include "pbd/stateful.h"
+#include "pbd/scoped_connections.h"
+
 #include "ardour/types.h"
 
 namespace ARDOUR {
@@ -36,7 +38,7 @@ class Track;
 class AudioTrack;
 class Session;
 
-class RouteGroup : public PBD::Stateful, public sigc::trackable {
+class RouteGroup : public PBD::Stateful, public PBD::ScopedConnectionList {
 public:
 	enum Flag {
 		Relative = 0x1,
@@ -126,8 +128,8 @@ public:
 
 	boost::shared_ptr<RouteList> route_list() { return routes; }
 
-	sigc::signal<void> changed;
-	sigc::signal<void,void*> FlagsChanged;
+	boost::signals2::signal<void()> changed;
+	boost::signals2::signal<void(void*)> FlagsChanged;
 
 	XMLNode& get_state ();
 	
diff --git a/libs/ardour/ardour/route_group_member.h b/libs/ardour/ardour/route_group_member.h
index 4b577121a6..8743423b18 100644
--- a/libs/ardour/ardour/route_group_member.h
+++ b/libs/ardour/ardour/route_group_member.h
@@ -20,7 +20,6 @@
 #ifndef __libardour_route_group_member_h__
 #define __libardour_route_group_member_h__
 
-#include <sigc++/signal.h>
 
 namespace ARDOUR  {
 
@@ -34,7 +33,7 @@ class RouteGroupMember
 
 	RouteGroup* route_group () const { return _route_group; }
 
-	sigc::signal<void> route_group_changed;
+	boost::signals2::signal<void()> route_group_changed;
 
   protected:
 	RouteGroup* _route_group;
diff --git a/libs/ardour/ardour/send.h b/libs/ardour/ardour/send.h
index 78a82820df..8b39d12727 100644
--- a/libs/ardour/ardour/send.h
+++ b/libs/ardour/ardour/send.h
@@ -20,7 +20,6 @@
 #ifndef __ardour_send_h__
 #define __ardour_send_h__
 
-#include <sigc++/signal.h>
 #include <string>
 
 #include "pbd/stateful.h"
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 192dc09908..273f251f3d 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -38,14 +38,12 @@
 #include "pbd/error.h"
 #include "pbd/rcu.h"
 #include "pbd/statefuldestructible.h"
+#include "pbd/scoped_connections.h"
 #include "pbd/undo.h"
 
 #include "midi++/mmc.h"
 #include "midi++/types.h"
 
-#include "pbd/destructible.h"
-#include "pbd/stateful.h"
-
 #include "ardour/ardour.h"
 #include "ardour/click.h"
 #include "ardour/chan_count.h"
@@ -120,7 +118,7 @@ class VSTPlugin;
 
 extern void setup_enum_writer ();
 
-class Session : public PBD::StatefulDestructible, public SessionEventManager, public boost::noncopyable
+class Session : public PBD::StatefulDestructible, public PBD::ScopedConnectionList, public SessionEventManager, public boost::noncopyable
 {
   public:
 	enum RecordState {
@@ -166,14 +164,14 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void set_deletion_in_progress ();
 	void clear_deletion_in_progress ();
 	bool deletion_in_progress() const { return _state_of_the_state & Deletion; }
-	sigc::signal<void> DirtyChanged;
+	boost::signals2::signal<void()> DirtyChanged;
 
 	const SessionDirectory& session_directory () const { return *(_session_dir.get()); }
 
-	static sigc::signal<void> AutoBindingOn;
-	static sigc::signal<void> AutoBindingOff;
+	static boost::signals2::signal<void()> AutoBindingOn;
+	static boost::signals2::signal<void()> AutoBindingOff;
 
-	static sigc::signal<void,std::string> Dialog;
+	static boost::signals2::signal<void(std::string)> Dialog;
 
 	std::string sound_dir (bool with_path = true) const;
 	std::string peak_dir () const;
@@ -274,29 +272,29 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 
 	/* Proxy signal for region hidden changes */
 
-	sigc::signal<void,boost::shared_ptr<Region> > RegionHiddenChange;
+	boost::signals2::signal<void(boost::shared_ptr<Region>)> RegionHiddenChange;
 
 	/* Emitted when all i/o connections are complete */
 
-	sigc::signal<void> IOConnectionsComplete;
+	boost::signals2::signal<void()> IOConnectionsComplete;
 
 	/* Record status signals */
 
-	sigc::signal<void> RecordStateChanged;
+	boost::signals2::signal<void()> RecordStateChanged;
 
 	/* Transport mechanism signals */
 
-	sigc::signal<void> TransportStateChange; /* generic */
-	sigc::signal<void,nframes64_t> PositionChanged; /* sent after any non-sequential motion */
-	sigc::signal<void> DurationChanged;
-	sigc::signal<void,nframes64_t> Xrun;
-	sigc::signal<void> TransportLooped;
+	boost::signals2::signal<void()> TransportStateChange; /* generic */
+	boost::signals2::signal<void(nframes64_t)> PositionChanged; /* sent after any non-sequential motion */
+	boost::signals2::signal<void()> DurationChanged;
+	boost::signals2::signal<void(nframes64_t)> Xrun;
+	boost::signals2::signal<void()> TransportLooped;
 
 	/** emitted when a locate has occurred */
-	sigc::signal<void> Located;
+	boost::signals2::signal<void()> Located;
 
-	sigc::signal<void,RouteList&> RouteAdded;
-	sigc::signal<void> RouteGroupChanged;
+	boost::signals2::signal<void(RouteList&)> RouteAdded;
+	boost::signals2::signal<void()> RouteGroupChanged;
 
 	void queue_event (SessionEvent*);
 
@@ -350,9 +348,9 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 
 	Locations *locations() { return &_locations; }
 
-	sigc::signal<void,Location*>    auto_loop_location_changed;
-	sigc::signal<void,Location*>    auto_punch_location_changed;
-	sigc::signal<void>              locations_modified;
+	boost::signals2::signal<void(Location*)>    auto_loop_location_changed;
+	boost::signals2::signal<void(Location*)>    auto_punch_location_changed;
+	boost::signals2::signal<void()>              locations_modified;
 
 	void set_auto_punch_location (Location *);
 	void set_auto_loop_location (Location *);
@@ -377,8 +375,8 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	static int rename_template (std::string old_name, std::string new_name);
 	static int delete_template (std::string name);
 
-	sigc::signal<void,std::string> StateSaved;
-	sigc::signal<void> StateReady;
+	boost::signals2::signal<void(std::string)> StateSaved;
+	boost::signals2::signal<void()> StateReady;
 
 	std::vector<std::string*>* possible_states() const;
 	static std::vector<std::string*>* possible_states (std::string path);
@@ -408,12 +406,12 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 
 	RouteGroup *route_group_by_name (std::string);
 
-	sigc::signal<void,RouteGroup*> route_group_added;
-	sigc::signal<void>             route_group_removed;
+	boost::signals2::signal<void(RouteGroup*)> route_group_added;
+	boost::signals2::signal<void()>             route_group_removed;
 
-	void foreach_route_group (sigc::slot<void,RouteGroup*> sl) {
+	void foreach_route_group (boost::function<void(RouteGroup*)> f) {
 		for (std::list<RouteGroup *>::iterator i = _route_groups.begin(); i != _route_groups.end(); i++) {
-			sl (*i);
+			f (*i);
 		}
 	}
 
@@ -478,9 +476,9 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 
 	nframes_t convert_to_frames_at (nframes_t position, AnyTime const &);
 
-	static sigc::signal<void> StartTimeChanged;
-	static sigc::signal<void> EndTimeChanged;
-	static sigc::signal<void> TimecodeOffsetChanged;
+	static boost::signals2::signal<void()> StartTimeChanged;
+	static boost::signals2::signal<void()> EndTimeChanged;
+	static boost::signals2::signal<void()> TimecodeOffsetChanged;
 
         std::vector<SyncSource> get_available_sync_options() const;
 	void   request_sync_source (Slave*);
@@ -498,15 +496,15 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	TempoMap& tempo_map() { return *_tempo_map; }
 
 	/// signals the current transport position in frames, bbt and timecode time (in that order)
-	sigc::signal<void, const nframes_t&, const BBT_Time&, const Timecode::Time&> tick;
+	boost::signals2::signal<void(const nframes_t&, const BBT_Time&, const Timecode::Time&)> tick;
 
 	/* region info  */
 
 	void add_regions (std::vector<boost::shared_ptr<Region> >&);
 
-	sigc::signal<void,boost::weak_ptr<Region> > RegionAdded;
-	sigc::signal<void,std::vector<boost::weak_ptr<Region> >& > RegionsAdded;
-	sigc::signal<void,boost::weak_ptr<Region> > RegionRemoved;
+	boost::signals2::signal<void(boost::weak_ptr<Region>)>              RegionAdded;
+	boost::signals2::signal<void(std::vector<boost::weak_ptr<Region> >&)> RegionsAdded;
+	boost::signals2::signal<void(boost::weak_ptr<Region>)>              RegionRemoved;
 
 	int region_name (std::string& result, std::string base = std::string(""), bool newlevel = false);
 	std::string new_region_name (std::string);
@@ -531,9 +529,9 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 
 	int  start_audio_export (nframes_t position, bool realtime);
 
-	sigc::signal<int, nframes_t> ProcessExport;
-	sigc::signal<void> ExportReadFinished;
-	static sigc::signal<void, std::string, std::string> Exported;
+	boost::signals2::signal<int(nframes_t)> ProcessExport;
+	boost::signals2::signal<void()> ExportReadFinished;
+	static boost::signals2::signal<void(std::string, std::string)> Exported;
 
 	void add_source (boost::shared_ptr<Source>);
 	void remove_source (boost::weak_ptr<Source>);
@@ -550,16 +548,16 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	    0 for "yes, delete this playlist",
 	    1 for "no, don't delete this playlist".
 	*/
-	sigc::signal<int,boost::shared_ptr<Playlist> > AskAboutPlaylistDeletion;
+	boost::signals2::signal<void(boost::shared_ptr<Playlist>)>  AskAboutPlaylistDeletion;
 
 	/** handlers should return 0 for "ignore the rate mismatch",
 	    !0 for "do not use this session"
 	*/
-	static sigc::signal<int,nframes_t, nframes_t> AskAboutSampleRateMismatch;
+	static boost::signals2::signal<int(nframes_t, nframes_t)> AskAboutSampleRateMismatch;
 
 	/** handlers should return !0 for use pending state, 0 for ignore it.
 	*/
-	static sigc::signal<int> AskAboutPendingState;
+	static boost::signals2::signal<int()> AskAboutPendingState;
 
 	boost::shared_ptr<AudioFileSource> create_audio_source_for_session (ARDOUR::AudioDiskstream&, uint32_t which_channel, bool destructive);
 
@@ -577,8 +575,8 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void remove_named_selection (NamedSelection *);
 
 	template<class T> void foreach_named_selection (T& obj, void (T::*func)(NamedSelection&));
-	sigc::signal<void> NamedSelectionAdded;
-	sigc::signal<void> NamedSelectionRemoved;
+	boost::signals2::signal<void()> NamedSelectionAdded;
+	boost::signals2::signal<void()> NamedSelectionRemoved;
 
 	/* Curves and AutomationLists (TODO when they go away) */
 	void add_automation_list(AutomationList*);
@@ -597,7 +595,7 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void cancel_audition ();
 	bool is_auditioning () const;
 
-	sigc::signal<void,bool> AuditionActive;
+	boost::signals2::signal<void(bool)> AuditionActive;
 
 	/* flattening stuff */
 
@@ -619,8 +617,8 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void set_listen (boost::shared_ptr<RouteList>, bool, SessionEvent::RTeventCallback after = rt_cleanup, bool group_override = false);
 	void set_record_enable (boost::shared_ptr<RouteList>, bool, SessionEvent::RTeventCallback after = rt_cleanup, bool group_override = false);
 
-	sigc::signal<void,bool> SoloActive;
-	sigc::signal<void> SoloChanged;
+	boost::signals2::signal<void(bool)> SoloActive;
+	boost::signals2::signal<void()> SoloChanged;
 	
 
 	/* control/master out */
@@ -658,8 +656,8 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void remove_bundle (boost::shared_ptr<Bundle>);
 	boost::shared_ptr<Bundle> bundle_by_name (std::string) const;
 
-	sigc::signal<void,boost::shared_ptr<Bundle> > BundleAdded;
-	sigc::signal<void,boost::shared_ptr<Bundle> > BundleRemoved;
+	boost::signals2::signal<void(boost::shared_ptr<Bundle>)> BundleAdded;
+	boost::signals2::signal<void(boost::shared_ptr<Bundle>)> BundleRemoved;
 
 	/* MIDI control */
 
@@ -673,10 +671,10 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	MIDI::Port *midi_port() const { return _midi_port; }
 	MIDI::Port *midi_clock_port() const { return _midi_clock_port; }
 
-	sigc::signal<void> MTC_PortChanged;
-	sigc::signal<void> MMC_PortChanged;
-	sigc::signal<void> MIDI_PortChanged;
-	sigc::signal<void> MIDIClock_PortChanged;
+	boost::signals2::signal<void()> MTC_PortChanged;
+	boost::signals2::signal<void()> MMC_PortChanged;
+	boost::signals2::signal<void()> MIDI_PortChanged;
+	boost::signals2::signal<void()> MIDIClock_PortChanged;
 
 	void set_trace_midi_input (bool, MIDI::Port* port = 0);
 	void set_trace_midi_output (bool, MIDI::Port* port = 0);
@@ -693,7 +691,7 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void stop_scrub ();
 	void set_scrub_speed (float);
 	nframes_t scrub_buffer_size() const;
-	sigc::signal<void> ScrubReady;
+	boost::signals2::signal<void()> ScrubReady;
 
 	/* History (for editors, mixers, UIs etc.) */
 
@@ -726,11 +724,11 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 		_current_trans.top()->add_command (cmd);
 	}
 
-	std::map<PBD::ID, PBD::StatefulThingWithGoingAway*> registry;
+	std::map<PBD::ID,PBD::StatefulDestructible*> registry;
 
 	// these commands are implemented in libs/ardour/session_command.cc
 	Command* memento_command_factory(XMLNode* n);
-	void register_with_memento_command_factory(PBD::ID, PBD::StatefulThingWithGoingAway*);
+	void register_with_memento_command_factory(PBD::ID, PBD::StatefulDestructible*);
 
 	/* clicking */
 
@@ -767,7 +765,7 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 			void* ptr,
 			float opt);
 
-	static sigc::signal<void> SendFeedback;
+	static boost::signals2::signal<void()> SendFeedback;
 
 	/* Controllables */
 
@@ -945,7 +943,7 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	int  stop_audio_export ();
 	void finalize_audio_export ();
 
-	sigc::connection export_freewheel_connection;
+	boost::signals2::scoped_connection export_freewheel_connection;
 
 	void prepare_diskstreams ();
 	void commit_diskstreams (nframes_t, bool& session_requires_butler);
@@ -1069,16 +1067,12 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	void              locations_added (Location*);
 	void              handle_locations_changed (Locations::LocationList&);
 
-	sigc::connection auto_punch_start_changed_connection;
-	sigc::connection auto_punch_end_changed_connection;
-	sigc::connection auto_punch_changed_connection;
+	PBD::ScopedConnectionList punch_connections;
 	void             auto_punch_start_changed (Location *);
 	void             auto_punch_end_changed (Location *);
 	void             auto_punch_changed (Location *);
 
-	sigc::connection auto_loop_start_changed_connection;
-	sigc::connection auto_loop_end_changed_connection;
-	sigc::connection auto_loop_changed_connection;
+	PBD::ScopedConnectionList loop_connections;
 	void             auto_loop_changed (Location *);
 
 	void first_stage_init (std::string path, std::string snapshot_name);
@@ -1143,7 +1137,7 @@ class Session : public PBD::StatefulDestructible, public SessionEventManager, pu
 	struct timeval last_mmc_step;
 	double step_speed;
 
-	typedef sigc::slot<bool> MidiTimeoutCallback;
+	typedef boost::function<bool()> MidiTimeoutCallback;
 	typedef std::list<MidiTimeoutCallback> MidiTimeoutList;
 
 	MidiTimeoutList midi_timeouts;
diff --git a/libs/ardour/ardour/session_event.h b/libs/ardour/ardour/session_event.h
index 1a3303087d..66c8720186 100644
--- a/libs/ardour/ardour/session_event.h
+++ b/libs/ardour/ardour/session_event.h
@@ -4,7 +4,6 @@
 #include <list>
 #include <boost/function.hpp>
 #include <boost/shared_ptr.hpp>
-#include <sigc++/signal.h>
 
 #include "pbd/pool.h"
 #include "pbd/ringbuffer.h"
diff --git a/libs/ardour/ardour/session_handle.h b/libs/ardour/ardour/session_handle.h
new file mode 100644
index 0000000000..c747ee9976
--- /dev/null
+++ b/libs/ardour/ardour/session_handle.h
@@ -0,0 +1,57 @@
+/*
+    Copyright (C) 2009 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#ifndef __libardour_session_handle_h__
+#define __libardour_session_handle_h__
+
+#include "pbd/scoped_connections.h"
+
+namespace ARDOUR {
+	class Session;
+
+class SessionHandleRef : public PBD::ScopedConnectionList
+{
+  public:
+	SessionHandleRef (ARDOUR::Session& s);
+	virtual ~SessionHandleRef () {}
+
+  protected:
+	ARDOUR::Session&          _session;
+	virtual void session_going_away ();
+};
+
+class SessionHandlePtr
+{
+  public:
+	SessionHandlePtr (ARDOUR::Session* s);
+	SessionHandlePtr () : _session (0) {}
+	virtual ~SessionHandlePtr () {}
+
+	virtual void set_session (ARDOUR::Session *);
+
+  protected:
+	ARDOUR::Session*          _session;
+	PBD::ScopedConnectionList _session_connections;
+
+	virtual void session_going_away ();
+};
+
+} /* namespace */
+
+#endif /* __libardour_session_handle_h__ */
diff --git a/libs/ardour/ardour/session_object.h b/libs/ardour/ardour/session_object.h
index 3a796c75b5..eb1a7c3e30 100644
--- a/libs/ardour/ardour/session_object.h
+++ b/libs/ardour/ardour/session_object.h
@@ -22,24 +22,26 @@
 
 #include <string>
 #include "pbd/statefuldestructible.h"
+#include "pbd/scoped_connections.h"
+
+#include "ardour/session_handle.h"
 
 namespace ARDOUR {
 
 class Session;
 
-/** An object associated with a Session.
- *
- * This is a few common things factored out of IO which weren't IO specific
- * (to fix the problem with e.g. PluginInsert being an IO which it shouldn't be).
+/** A named object associated with a Session. Objects derived from this class are
+    expected to be destroyed before the session calls drop_references().
  */
-class SessionObject : public PBD::StatefulDestructible
+
+class SessionObject : public SessionHandleRef, public PBD::StatefulDestructible
 {
-public:
-	SessionObject(Session& session, const std::string& name)
-		: _session(session)
+  public:
+	SessionObject (Session& session, const std::string& name)
+		: SessionHandleRef (session)
 		, _name(name)
 	{}
-
+	
 	Session&           session() const { return _session; }
 	const std::string& name()    const { return _name; }
 
@@ -51,10 +53,9 @@ public:
 		return true;
 	}
 
-	sigc::signal<void> NameChanged;
+	boost::signals2::signal<void()> NameChanged;
 
-protected:
-	Session&    _session;
+  protected:
 	std::string _name;
 };
 
diff --git a/libs/ardour/ardour/session_playlists.h b/libs/ardour/ardour/session_playlists.h
index 83f469cfd4..8870794cc0 100644
--- a/libs/ardour/ardour/session_playlists.h
+++ b/libs/ardour/ardour/session_playlists.h
@@ -25,7 +25,9 @@
 #include <string>
 #include <glibmm/thread.h>
 #include <boost/shared_ptr.hpp>
-#include <sigc++/trackable.h>
+#include <boost/function.hpp>
+
+#include "pbd/scoped_connections.h"
 
 class XMLNode;
 
@@ -36,7 +38,7 @@ class Region;
 class Source;
 class Session;
 	
-class SessionPlaylists : public sigc::trackable
+class SessionPlaylists : public PBD::ScopedConnectionList
 {
 public:
 	~SessionPlaylists ();
@@ -58,7 +60,7 @@ private:
 	void find_equivalent_playlist_regions (boost::shared_ptr<Region>, std::vector<boost::shared_ptr<Region> >& result);
 	void update_after_tempo_map_change ();
 	void add_state (XMLNode *, bool);
-	bool maybe_delete_unused (sigc::signal<int, boost::shared_ptr<Playlist> >);
+	bool maybe_delete_unused (boost::function<int(boost::shared_ptr<Playlist>)>);
 	int load (Session &, const XMLNode&);
 	int load_unused (Session &, const XMLNode&);
 	boost::shared_ptr<Playlist> XMLPlaylistFactory (Session &, const XMLNode&);
diff --git a/libs/ardour/ardour/slave.h b/libs/ardour/ardour/slave.h
index 1125e920a0..4fe8e1ec46 100644
--- a/libs/ardour/ardour/slave.h
+++ b/libs/ardour/ardour/slave.h
@@ -23,10 +23,12 @@
 #include <vector>
 
 #include <glibmm/thread.h>
+#include <boost/signals2.hpp>
 
 #include <jack/jack.h>
 
-#include <sigc++/signal.h>
+#include "pbd/scoped_connections.h"
+
 #include "ardour/types.h"
 #include "midi++/parser.h"
 #include "midi++/types.h"
@@ -220,7 +222,7 @@ struct SafeTime {
     }
 };
 
-class MTC_Slave : public Slave, public sigc::trackable {
+class MTC_Slave : public Slave {
   public:
 	MTC_Slave (Session&, MIDI::Port&);
 	~MTC_Slave ();
@@ -240,7 +242,7 @@ class MTC_Slave : public Slave, public sigc::trackable {
   private:
 	Session&    session;
 	MIDI::Port* port;
-	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList* port_connections;
 	bool        can_notify_on_unknown_rate;
 	PIChaser* pic;
 
@@ -277,7 +279,7 @@ class MTC_Slave : public Slave, public sigc::trackable {
 	void process_apparent_speed (double);
 };
 
-class MIDIClock_Slave : public Slave, public sigc::trackable {
+class MIDIClock_Slave : public Slave {
   public:
 	MIDIClock_Slave (Session&, MIDI::Port&, int ppqn = 24);
 
@@ -301,7 +303,7 @@ class MIDIClock_Slave : public Slave, public sigc::trackable {
   private:
 	ISlaveSessionProxy* session;
 	MIDI::Port* port;
-	std::vector<sigc::connection> connections;
+	PBD::ScopedConnectionList* port_connections;
 
 	/// pulses per quarter note for one MIDI clock frame (default 24)
 	int         ppqn;
diff --git a/libs/ardour/ardour/source.h b/libs/ardour/ardour/source.h
index b2e1381e43..a7a6e2207c 100644
--- a/libs/ardour/ardour/source.h
+++ b/libs/ardour/ardour/source.h
@@ -24,7 +24,6 @@
 #include <set>
 
 #include <boost/utility.hpp>
-#include <sigc++/signal.h>
 #include "pbd/statefuldestructible.h"
 
 #include "ardour/ardour.h"
@@ -82,15 +81,15 @@ class Source : public SessionObject, public boost::noncopyable
 	virtual bool set_destructive (bool /*yn*/) { return false; }
 	virtual bool length_mutable() const    { return false; }
 
-	static sigc::signal<void,Source*>             SourceCreated;
-	sigc::signal<void,boost::shared_ptr<Source> > Switched;
+	static boost::signals2::signal<void(Source*)>             SourceCreated;
+	boost::signals2::signal<void(boost::shared_ptr<Source>)> Switched;
 
 	bool has_been_analysed() const;
 	virtual bool can_be_analysed() const { return false; }
 	virtual void set_been_analysed (bool yn);
 	virtual bool check_for_analysis_data_on_disk();
 
-	sigc::signal<void> AnalysisChanged;
+	boost::signals2::signal<void()> AnalysisChanged;
 
 	AnalysisFeatureList transients;
 	std::string get_transients_path() const;
diff --git a/libs/ardour/ardour/source_factory.h b/libs/ardour/ardour/source_factory.h
index 21af4ece75..4da285e980 100644
--- a/libs/ardour/ardour/source_factory.h
+++ b/libs/ardour/ardour/source_factory.h
@@ -22,7 +22,6 @@
 
 #include <string>
 #include <stdint.h>
-#include <sigc++/sigc++.h>
 #include <boost/shared_ptr.hpp>
 
 #include "ardour/source.h"
@@ -38,7 +37,7 @@ class SourceFactory {
   public:
 	static void init ();
 
-	static sigc::signal<void,boost::shared_ptr<Source> > SourceCreated;
+	static boost::signals2::signal<void(boost::shared_ptr<Source>)> SourceCreated;
 
 	static boost::shared_ptr<Source> create (Session&, const XMLNode& node, bool async = false);
 	static boost::shared_ptr<Source> createSilent (Session&, const XMLNode& node,
diff --git a/libs/ardour/ardour/tempo.h b/libs/ardour/ardour/tempo.h
index 28c974bff1..ba7bbbcf7e 100644
--- a/libs/ardour/ardour/tempo.h
+++ b/libs/ardour/ardour/tempo.h
@@ -30,7 +30,6 @@
 #include "pbd/stateful.h"
 #include "pbd/statefuldestructible.h"
 
-#include <sigc++/signal.h>
 
 #include "ardour/ardour.h"
 
@@ -259,7 +258,7 @@ class TempoMap : public PBD::StatefulDestructible
 
 	nframes_t frame_rate () const { return _frame_rate; }
 
-	sigc::signal<void,ARDOUR::Change> StateChanged;
+	boost::signals2::signal<void(ARDOUR::Change)> StateChanged;
 
   private:
 	static Tempo    _default_tempo;
diff --git a/libs/ardour/ardour/ticker.h b/libs/ardour/ardour/ticker.h
index 3e0f1844a6..9a26d4d3ff 100644
--- a/libs/ardour/ardour/ticker.h
+++ b/libs/ardour/ardour/ticker.h
@@ -18,10 +18,13 @@
     $Id$
 */
 
-#include <sigc++/sigc++.h>
 
-#include "ardour/types.h"
 #include "midi++/jack.h"
+#include "pbd/scoped_connections.h"
+
+#include "ardour/types.h"
+#include "ardour/session_handle.h"
+
 
 #ifndef TICKER_H_
 #define TICKER_H_
@@ -31,22 +34,18 @@ namespace ARDOUR
 
 class Session;
 
-class Ticker : public sigc::trackable
+class Ticker : public SessionHandlePtr
 {
 public:
-	Ticker() : _session(0) {};
-	virtual ~Ticker() {};
+	Ticker() {};
+	virtual ~Ticker() {}
 
 	virtual void tick(
 		const nframes_t& transport_frames,
 		const BBT_Time& transport_bbt,
 		const Timecode::Time& transport_timecode) = 0;
 
-	virtual void set_session(Session& s);
-	virtual void going_away() { _session = 0; }
-
-protected:
-	Session* _session;
+	void set_session (Session* s);
 };
 
 class MidiClockTicker : public Ticker
@@ -70,8 +69,8 @@ public:
 		const BBT_Time& transport_bbt,
 		const Timecode::Time& transport_timecode);
 
-	void set_session(Session& s);
-	void going_away() { _midi_port = 0; Ticker::going_away(); }
+	void set_session (Session* s);
+	void session_going_away();
 
 	/// slot for the signal session::MIDIClock_PortChanged
 	void update_midi_clock_port();
diff --git a/libs/ardour/ardour/track.h b/libs/ardour/ardour/track.h
index 5d8e2dbbd5..c23e159684 100644
--- a/libs/ardour/ardour/track.h
+++ b/libs/ardour/ardour/track.h
@@ -43,7 +43,7 @@ class Track : public Route
 	TrackMode mode () const { return _mode; }
 	virtual int set_mode (TrackMode /*m*/) { return false; }
 	virtual bool can_use_mode (TrackMode /*m*/, bool& /*bounce_required*/) { return false; }
-	sigc::signal<void> TrackModeChanged;
+	boost::signals2::signal<void()> TrackModeChanged;
 
 	virtual int no_roll (nframes_t nframes, sframes_t start_frame, sframes_t end_frame,
 			bool state_changing, bool can_record, bool rec_monitors_input);
@@ -90,8 +90,8 @@ class Track : public Route
 	bool record_enabled() const;
 	void set_record_enable (bool yn, void *src);
 
-	sigc::signal<void> DiskstreamChanged;
-	sigc::signal<void> FreezeChange;
+	boost::signals2::signal<void()> DiskstreamChanged;
+	boost::signals2::signal<void()> FreezeChange;
 
   protected:
 	Track (Session& sess, const XMLNode& node, DataType default_type = DataType::AUDIO);
@@ -141,7 +141,7 @@ class Track : public Route
 
 	FreezeRecord          _freeze_record;
 	XMLNode*              pending_state;
-	sigc::connection      recenable_connection;
+	boost::signals2::scoped_connection  recenable_connection;
 	bool                  _destructive;
 
 	boost::shared_ptr<RecEnableControllable> _rec_enable_control;
diff --git a/libs/ardour/ardour/vst_plugin.h b/libs/ardour/ardour/vst_plugin.h
index 2d9875df57..753d94294f 100644
--- a/libs/ardour/ardour/vst_plugin.h
+++ b/libs/ardour/ardour/vst_plugin.h
@@ -27,7 +27,6 @@
 #include <string>
 #include <dlfcn.h>
 
-#include <sigc++/signal.h>
 #include "pbd/stateful.h"
 #include <jack/types.h>
 #include "ardour/plugin.h"
diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index 40411f4133..2ad323ca1c 100644
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -126,8 +126,6 @@ AudioDiskstream::~AudioDiskstream ()
 {
 	DEBUG_TRACE (DEBUG::Destruction, string_compose ("Audio Diskstream %1 destructor\n", _name));
 
-	notify_callbacks ();
-
 	{
 		RCUWriter<ChannelList> writer (channels);
 		boost::shared_ptr<ChannelList> c = writer.get_copy();
@@ -1506,7 +1504,7 @@ AudioDiskstream::transport_stopped (struct tm& when, time_t twhen, bool abort_ca
 				continue; /* XXX is this OK? */
 			}
 
-			region->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Diskstream::remove_region_from_last_capture), boost::weak_ptr<Region>(region)));
+			scoped_connect (region->GoingAway, boost::bind (&Diskstream::remove_region_from_last_capture, this, boost::weak_ptr<Region>(region)));
 
 			_last_capture_regions.push_back (region);
 
diff --git a/libs/ardour/audio_playlist.cc b/libs/ardour/audio_playlist.cc
index 63013426cb..acb44e43c4 100644
--- a/libs/ardour/audio_playlist.cc
+++ b/libs/ardour/audio_playlist.cc
@@ -21,7 +21,6 @@
 
 #include <cstdlib>
 
-#include <sigc++/bind.h>
 
 #include "ardour/types.h"
 #include "ardour/configuration.h"
@@ -103,12 +102,10 @@ AudioPlaylist::AudioPlaylist (boost::shared_ptr<const AudioPlaylist> other, nfra
 
 AudioPlaylist::~AudioPlaylist ()
 {
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 
 	/* drop connections to signals */
 
-	notify_callbacks ();
-
 	_crossfades.clear ();
 }
 
@@ -531,8 +528,8 @@ AudioPlaylist::add_crossfade (boost::shared_ptr<Crossfade> xfade)
 	} else {
 		_crossfades.push_back (xfade);
 
-		xfade->Invalidated.connect (sigc::mem_fun (*this, &AudioPlaylist::crossfade_invalidated));
-		xfade->StateChanged.connect (sigc::mem_fun (*this, &AudioPlaylist::crossfade_changed));
+		scoped_connect (xfade->Invalidated, boost::bind (&AudioPlaylist::crossfade_invalidated, this, _1));
+		scoped_connect (xfade->StateChanged, boost::bind (&AudioPlaylist::crossfade_changed, this, _1));
 
 		notify_crossfade_added (xfade);
 	}
@@ -587,8 +584,8 @@ AudioPlaylist::set_state (const XMLNode& node, int version)
 		try {
 			boost::shared_ptr<Crossfade> xfade = boost::shared_ptr<Crossfade> (new Crossfade (*((const Playlist *)this), *child));
 			_crossfades.push_back (xfade);
-			xfade->Invalidated.connect (sigc::mem_fun (*this, &AudioPlaylist::crossfade_invalidated));
-			xfade->StateChanged.connect (sigc::mem_fun (*this, &AudioPlaylist::crossfade_changed));
+			scoped_connect (xfade->Invalidated, boost::bind (&AudioPlaylist::crossfade_invalidated, this, _1));
+			scoped_connect (xfade->StateChanged, boost::bind (&AudioPlaylist::crossfade_changed, this, _1));
 			NewCrossfade(xfade);
 		}
 
@@ -791,7 +788,7 @@ AudioPlaylist::crossfades_at (nframes_t frame, Crossfades& clist)
 }
 
 void
-AudioPlaylist::foreach_crossfade (sigc::slot<void, boost::shared_ptr<Crossfade> > s)
+AudioPlaylist::foreach_crossfade (boost::function<void (boost::shared_ptr<Crossfade>)> s)
 {
 	RegionLock rl (this, false);
 	for (Crossfades::iterator i = _crossfades.begin(); i != _crossfades.end(); ++i) {
diff --git a/libs/ardour/audio_playlist_importer.cc b/libs/ardour/audio_playlist_importer.cc
index cb6bbed907..3f773fc0a9 100644
--- a/libs/ardour/audio_playlist_importer.cc
+++ b/libs/ardour/audio_playlist_importer.cc
@@ -170,7 +170,7 @@ AudioPlaylistImporter::_prepare_move ()
 {
 	// Rename
 	while (session.playlists->by_name (name) || !handler.check_name (name)) {
-		std::pair<bool, string> rename_pair = Rename (_("A playlist with this name already exists, please rename it."), name);
+		std::pair<bool, string> rename_pair = *Rename (_("A playlist with this name already exists, please rename it."), name);
 		if (!rename_pair.first) {
 			return false;
 		}
diff --git a/libs/ardour/audio_track.cc b/libs/ardour/audio_track.cc
index 68081661ad..736fe41738 100644
--- a/libs/ardour/audio_track.cc
+++ b/libs/ardour/audio_track.cc
@@ -17,9 +17,6 @@
 
 */
 
-#include <sigc++/retype.h>
-#include <sigc++/retype_return.h>
-#include <sigc++/bind.h>
 
 #include "pbd/error.h"
 #include "pbd/enumwriter.h"
@@ -185,7 +182,7 @@ AudioTrack::set_diskstream (boost::shared_ptr<AudioDiskstream> ds, void * /*src*
 	if (audio_diskstream()->deprecated_io_node) {
 
 		if (!IO::connecting_legal) {
-			IO::ConnectingLegal.connect (sigc::mem_fun (*this, &AudioTrack::deprecated_use_diskstream_connections));
+			scoped_connect (IO::ConnectingLegal, boost::bind (&AudioTrack::deprecated_use_diskstream_connections, this));
 		} else {
 			deprecated_use_diskstream_connections ();
 		}
@@ -307,7 +304,7 @@ AudioTrack::_set_state (const XMLNode& node, int version, bool call_base)
 	pending_state = const_cast<XMLNode*> (&node);
 
 	if (_session.state_of_the_state() & Session::Loading) {
-		_session.StateReady.connect (sigc::mem_fun (*this, &AudioTrack::set_state_part_two));
+		scoped_connect (_session.StateReady, boost::bind (&AudioTrack::set_state_part_two, this));
 	} else {
 		set_state_part_two ();
 	}
diff --git a/libs/ardour/audio_track_importer.cc b/libs/ardour/audio_track_importer.cc
index 146722b3c0..aad20f9317 100644
--- a/libs/ardour/audio_track_importer.cc
+++ b/libs/ardour/audio_track_importer.cc
@@ -240,7 +240,7 @@ AudioTrackImporter::_prepare_move ()
 	/* Rename */
 
 	while (session.route_by_name (name) || !track_handler.check_name (name)) {
-		std::pair<bool, string> rename_pair = Rename (_("A playlist with this name already exists, please rename it."), name);
+		std::pair<bool, string> rename_pair = *Rename (_("A playlist with this name already exists, please rename it."), name);
 		if (!rename_pair.first) {
 			return false;
 		}
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 2c16c52296..b1c5527570 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -66,7 +66,6 @@ AudioEngine::AudioEngine (string client_name)
 {
 	_instance = this; /* singleton */
 
-	session = 0;
 	session_remove_pending = false;
 	_running = false;
 	_has_run = false;
@@ -158,24 +157,24 @@ AudioEngine::start ()
 
 		nframes_t blocksize = jack_get_buffer_size (_priv_jack);
 
-		if (session) {
+		if (_session) {
 			BootMessage (_("Connect session to engine"));
 
-			session->set_block_size (blocksize);
-			session->set_frame_rate (jack_get_sample_rate (_priv_jack));
+			_session->set_block_size (blocksize);
+			_session->set_frame_rate (jack_get_sample_rate (_priv_jack));
 
 			/* page in as much of the session process code as we
 			   can before we really start running.
 			*/
 
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
-			session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
+			_session->process (blocksize);
 		}
 
 		_processed_frames = 0;
@@ -192,7 +191,7 @@ AudioEngine::start ()
 		jack_set_freewheel_callback (_priv_jack, _freewheel_callback, this);
 		jack_set_port_registration_callback (_priv_jack, _registration_callback, this);
 
-		if (session && session->config.get_jack_time_master()) {
+		if (_session && _session->config.get_jack_time_master()) {
 			jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
 		}
 
@@ -269,8 +268,8 @@ void
 AudioEngine::jack_timebase_callback (jack_transport_state_t state, nframes_t nframes,
 				     jack_position_t* pos, int new_position)
 {
-	if (_jack && session && session->synced_to_jack()) {
-		session->jack_timebase_callback (state, nframes, pos, new_position);
+	if (_jack && _session && _session->synced_to_jack()) {
+		_session->jack_timebase_callback (state, nframes, pos, new_position);
 	}
 }
 
@@ -283,8 +282,8 @@ AudioEngine::_jack_sync_callback (jack_transport_state_t state, jack_position_t*
 int
 AudioEngine::jack_sync_callback (jack_transport_state_t state, jack_position_t* pos)
 {
-	if (_jack && session) {
-		return session->jack_sync_callback (state, pos);
+	if (_jack && _session) {
+		return _session->jack_sync_callback (state, pos);
 	}
 
 	return true;
@@ -372,7 +371,7 @@ AudioEngine::process_callback (nframes_t nframes)
 		next_processed_frames = _processed_frames + nframes;
 	}
 
-	if (!tm.locked() || session == 0) {
+	if (!tm.locked() || _session == 0) {
 		/* return having done nothing */
 		_processed_frames = next_processed_frames;
 		return 0;
@@ -380,7 +379,7 @@ AudioEngine::process_callback (nframes_t nframes)
 
 	if (session_remove_pending) {
 		/* perform the actual session removal */
-		session = 0;
+		_session = 0;
 		session_remove_pending = false;
 		session_removed.signal();
 		_processed_frames = next_processed_frames;
@@ -402,14 +401,16 @@ AudioEngine::process_callback (nframes_t nframes)
 	}
 
 	if (_freewheeling) {
-		/* emit the Freewheel signal and stop freewheeling in the event of trouble */
-		if (Freewheel (nframes)) {
+		/* emit the Freewheel signal and stop freewheeling in the event of trouble 
+		 * the indirection is to pick up the return value of the signal.
+		 */
+		if (*Freewheel (nframes)) {
 			jack_set_freewheel (_priv_jack, false);
 		}
 
 	} else {
-		if (session) {
-			session->process (nframes);
+		if (_session) {
+			_session->process (nframes);
 		}
 	}
 
@@ -442,7 +443,7 @@ AudioEngine::process_callback (nframes_t nframes)
 		last_monitor_check = next_processed_frames;
 	}
 
-	if (session->silent()) {
+	if (_session->silent()) {
 
 		boost::shared_ptr<Ports> p = ports.reader();
 
@@ -483,8 +484,8 @@ AudioEngine::jack_sample_rate_callback (nframes_t nframes)
 	monitor_check_interval = nframes / 10;
 	last_monitor_check = 0;
 
-	if (session) {
-		session->set_frame_rate (nframes);
+	if (_session) {
+		_session->set_frame_rate (nframes);
 	}
 
 	SampleRateChanged (nframes); /* EMIT SIGNAL */
@@ -514,8 +515,8 @@ AudioEngine::jack_bufsize_callback (nframes_t nframes)
 		(*i)->reset();
 	}
 
-	if (session) {
-		session->set_block_size (_buffer_size);
+	if (_session) {
+		_session->set_block_size (_buffer_size);
 	}
 
 	return 0;
@@ -536,7 +537,7 @@ AudioEngine::start_metering_thread ()
 {
 	if (m_meter_thread == 0) {
 		g_atomic_int_set (&m_meter_exit, 0);
-		m_meter_thread = Glib::Thread::create (sigc::mem_fun(this, &AudioEngine::meter_thread),
+		m_meter_thread = Glib::Thread::create (boost::bind (&AudioEngine::meter_thread, this),
 						       500000, true, true, Glib::THREAD_PRIORITY_NORMAL);
 	}
 }
@@ -558,31 +559,31 @@ AudioEngine::set_session (Session *s)
 {
 	Glib::Mutex::Lock pl (_process_lock);
 
-	if (!session) {
-
-		session = s;
+	SessionHandlePtr::set_session (s);
 
+	if (_session) {
+		
 		nframes_t blocksize = jack_get_buffer_size (_jack);
-
+		
 		/* page in as much of the session process code as we
 		   can before we really start running.
 		*/
-
+		
 		boost::shared_ptr<Ports> p = ports.reader();
-
+		
 		for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
 			(*i)->cycle_start (blocksize);
 		}
-
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-		s->process (blocksize);
-
+		
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		_session->process (blocksize);
+		
 		for (Ports::iterator i = p->begin(); i != p->end(); ++i) {
 			(*i)->cycle_end (blocksize);
 		}
@@ -596,13 +597,13 @@ AudioEngine::remove_session ()
 
 	if (_running) {
 
-		if (session) {
+		if (_session) {
 			session_remove_pending = true;
 			session_removed.wait(_process_lock);
 		}
 
 	} else {
-		session = 0;
+		SessionHandlePtr::set_session (0);
 	}
 
 	remove_all_ports ();
@@ -1081,8 +1082,8 @@ int
 AudioEngine::reset_timebase ()
 {
         GET_PRIVATE_JACK_POINTER_RET (_jack, -1);
-	if (session) {
-		if (session->config.get_jack_time_master()) {
+	if (_session) {
+		if (_session->config.get_jack_time_master()) {
 			return jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
 		} else {
 			return jack_release_timebase (_jack);
@@ -1214,11 +1215,11 @@ AudioEngine::reconnect_to_jack ()
 
         GET_PRIVATE_JACK_POINTER_RET (_jack,-1);
 
-	if (session) {
-		session->reset_jack_connection (_priv_jack);
+	if (_session) {
+		_session->reset_jack_connection (_priv_jack);
 		nframes_t blocksize = jack_get_buffer_size (_priv_jack);
-		session->set_block_size (blocksize);
-		session->set_frame_rate (jack_get_sample_rate (_priv_jack));
+		_session->set_block_size (blocksize);
+		_session->set_frame_rate (jack_get_sample_rate (_priv_jack));
 
 		_raw_buffer_sizes[DataType::AUDIO] = blocksize * sizeof(float);
 		cout << "FIXME: Assuming maximum MIDI buffer size " << blocksize * 4 << "bytes" << endl;
@@ -1237,7 +1238,7 @@ AudioEngine::reconnect_to_jack ()
 	jack_set_sync_callback (_priv_jack, _jack_sync_callback, this);
 	jack_set_freewheel_callback (_priv_jack, _freewheel_callback, this);
 
-	if (session && session->config.get_jack_time_master()) {
+	if (_session && _session->config.get_jack_time_master()) {
 		jack_set_timebase_callback (_priv_jack, 0, _jack_timebase_callback, this);
 	}
 
diff --git a/libs/ardour/audiofilesource.cc b/libs/ardour/audiofilesource.cc
index b840c3a7c9..1500b139ac 100644
--- a/libs/ardour/audiofilesource.cc
+++ b/libs/ardour/audiofilesource.cc
@@ -70,7 +70,7 @@ using namespace Glib;
 
 ustring AudioFileSource::peak_dir = "";
 
-sigc::signal<void> AudioFileSource::HeaderPositionOffsetChanged;
+boost::signals2::signal<void()> AudioFileSource::HeaderPositionOffsetChanged;
 uint64_t           AudioFileSource::header_position_offset = 0;
 
 /* XXX maybe this too */
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index d660616bb3..ac173db546 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -24,8 +24,6 @@
 
 #include <set>
 
-#include <sigc++/bind.h>
-#include <sigc++/class_slot.h>
 
 #include <glibmm/thread.h>
 
@@ -98,7 +96,7 @@ AudioRegion::AudioRegion (boost::shared_ptr<AudioSource> src, nframes_t start, n
 {
 	boost::shared_ptr<AudioFileSource> afs = boost::dynamic_pointer_cast<AudioFileSource> (src);
 	if (afs) {
-		afs->HeaderPositionOffsetChanged.connect (sigc::mem_fun (*this, &AudioRegion::source_offset_changed));
+		scoped_connect (afs->HeaderPositionOffsetChanged, boost::bind (&AudioRegion::source_offset_changed, this));
 	}
 
 	init ();
@@ -115,7 +113,7 @@ AudioRegion::AudioRegion (boost::shared_ptr<AudioSource> src, nframes_t start, n
 {
 	boost::shared_ptr<AudioFileSource> afs = boost::dynamic_pointer_cast<AudioFileSource> (src);
 	if (afs) {
-		afs->HeaderPositionOffsetChanged.connect (sigc::mem_fun (*this, &AudioRegion::source_offset_changed));
+		scoped_connect (afs->HeaderPositionOffsetChanged, boost::bind (&AudioRegion::source_offset_changed, this));
 	}
 
 	init ();
@@ -207,7 +205,7 @@ AudioRegion::AudioRegion (boost::shared_ptr<const AudioRegion> other, const Sour
 
 		boost::shared_ptr<AudioFileSource> afs = boost::dynamic_pointer_cast<AudioFileSource> ((*i));
 		if (afs) {
-			afs->HeaderPositionOffsetChanged.connect (sigc::mem_fun (*this, &AudioRegion::source_offset_changed));
+			scoped_connect (afs->HeaderPositionOffsetChanged, boost::bind (&AudioRegion::source_offset_changed, this));
 		}
 	}
 
@@ -231,7 +229,7 @@ AudioRegion::AudioRegion (boost::shared_ptr<AudioSource> src, const XMLNode& nod
 {
 	boost::shared_ptr<AudioFileSource> afs = boost::dynamic_pointer_cast<AudioFileSource> (src);
 	if (afs) {
-		afs->HeaderPositionOffsetChanged.connect (sigc::mem_fun (*this, &AudioRegion::source_offset_changed));
+		scoped_connect (afs->HeaderPositionOffsetChanged, boost::bind (&AudioRegion::source_offset_changed, this));
 	}
 
 	init ();
@@ -272,7 +270,7 @@ void
 AudioRegion::connect_to_analysis_changed ()
 {
 	for (SourceList::const_iterator i = _sources.begin(); i != _sources.end(); ++i) {
-		(*i)->AnalysisChanged.connect (sigc::mem_fun (*this, &AudioRegion::invalidate_transients));
+		scoped_connect ((*i)->AnalysisChanged, boost::bind (&AudioRegion::invalidate_transients, this));
 	}
 }
 
@@ -287,7 +285,7 @@ AudioRegion::connect_to_header_position_offset_changed ()
 			unique_srcs.insert (*i);
 			boost::shared_ptr<AudioFileSource> afs = boost::dynamic_pointer_cast<AudioFileSource> (*i);
 			if (afs) {
-				afs->HeaderPositionOffsetChanged.connect (sigc::mem_fun (*this, &AudioRegion::source_offset_changed));
+				scoped_connect (afs->HeaderPositionOffsetChanged, boost::bind (&AudioRegion::source_offset_changed, this));
 			}
 		}
 	}
@@ -296,9 +294,9 @@ AudioRegion::connect_to_header_position_offset_changed ()
 void
 AudioRegion::listen_to_my_curves ()
 {
-	_envelope->StateChanged.connect (sigc::mem_fun (*this, &AudioRegion::envelope_changed));
-	_fade_in->StateChanged.connect (sigc::mem_fun (*this, &AudioRegion::fade_in_changed));
-	_fade_out->StateChanged.connect (sigc::mem_fun (*this, &AudioRegion::fade_out_changed));
+	scoped_connect (_envelope->StateChanged, boost::bind (&AudioRegion::envelope_changed, this));
+	scoped_connect (_fade_in->StateChanged, boost::bind (&AudioRegion::fade_in_changed, this));
+	scoped_connect (_fade_out->StateChanged, boost::bind (&AudioRegion::fade_out_changed, this));
 }
 
 void
diff --git a/libs/ardour/audiosource.cc b/libs/ardour/audiosource.cc
index f7d6088aec..fd481c9730 100644
--- a/libs/ardour/audiosource.cc
+++ b/libs/ardour/audiosource.cc
@@ -149,7 +149,7 @@ AudioSource::update_length (sframes_t pos, sframes_t cnt)
  ***********************************************************************/
 
 bool
-AudioSource::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) const
+AudioSource::peaks_ready (boost::function<void()> doThisWhenReady, boost::signals2::connection& connect_here_if_not) const
 {
 	bool ret;
 	Glib::Mutex::Lock lm (_peaks_ready_lock);
@@ -159,7 +159,7 @@ AudioSource::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) con
 	*/
 
 	if (!(ret = _peaks_built)) {
-		conn = PeaksReady.connect (the_slot);
+		connect_here_if_not = PeaksReady.connect (doThisWhenReady);
 	}
 
 	return ret;
diff --git a/libs/ardour/auditioner.cc b/libs/ardour/auditioner.cc
index dbb76c005e..7d353a1bdd 100644
--- a/libs/ardour/auditioner.cc
+++ b/libs/ardour/auditioner.cc
@@ -72,7 +72,7 @@ Auditioner::Auditioner (Session& s)
 	_main_outs->allow_pan_reset ();
 	_main_outs->reset_panner ();
 
-	_output->changed.connect (sigc::mem_fun (*this, &Auditioner::output_changed));
+	scoped_connect (_output->changed, boost::bind (&Auditioner::output_changed, this, _1, _2));
 
 	the_region.reset ((AudioRegion*) 0);
 	g_atomic_int_set (&_active, 0);
diff --git a/libs/ardour/automation_list.cc b/libs/ardour/automation_list.cc
index db8f5bb799..9a6eb08e45 100644
--- a/libs/ardour/automation_list.cc
+++ b/libs/ardour/automation_list.cc
@@ -23,7 +23,6 @@
 #include <cmath>
 #include <sstream>
 #include <algorithm>
-#include <sigc++/bind.h>
 #include "ardour/automation_list.h"
 #include "ardour/event_type_map.h"
 #include "evoral/Curve.hpp"
@@ -36,7 +35,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,AutomationList *> AutomationList::AutomationListCreated;
+boost::signals2::signal<void(AutomationList *)> AutomationList::AutomationListCreated;
 
 #if 0
 static void dumpit (const AutomationList& al, string prefix = "")
@@ -113,7 +112,7 @@ AutomationList::AutomationList (const XMLNode& node, Evoral::Parameter id)
 
 AutomationList::~AutomationList()
 {
-	GoingAway ();
+	drop_references ();
 }
 
 boost::shared_ptr<Evoral::ControlList>
diff --git a/libs/ardour/butler.cc b/libs/ardour/butler.cc
index 05ac7316ec..2fd4c1d9c1 100644
--- a/libs/ardour/butler.cc
+++ b/libs/ardour/butler.cc
@@ -38,8 +38,8 @@ static float _write_data_rate;
 
 namespace ARDOUR {
 
-Butler::Butler(Session* s)
-	: session(s)
+Butler::Butler(Session& s)
+	: SessionHandleRef (s)
 	, thread(0)
 	, audio_dstream_buffer_size(0)
 	, midi_dstream_buffer_size(0)
@@ -54,7 +54,7 @@ Butler::~Butler()
 int
 Butler::start_thread()
 {
-	const float rate = (float)session->frame_rate();
+	const float rate = (float)_session.frame_rate();
 
 	/* size is in Samples, not bytes */
 	audio_dstream_buffer_size = (uint32_t) floor (Config->get_audio_track_buffer_seconds() * rate);
@@ -194,7 +194,7 @@ Butler::thread_work ()
 		}
 
 		if (transport_work_requested()) {
-			session->butler_transport_work ();
+			_session.butler_transport_work ();
 		}
 
 		disk_work_outstanding = false;
@@ -203,7 +203,7 @@ Butler::thread_work ()
 
 		begin = get_microseconds();
 
-		boost::shared_ptr<Session::DiskstreamList> dsl = session->diskstream_list().reader ();
+		boost::shared_ptr<Session::DiskstreamList> dsl = _session.diskstream_list().reader ();
 
 //		for (i = dsl->begin(); i != dsl->end(); ++i) {
 //			cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
@@ -285,11 +285,11 @@ Butler::thread_work ()
 			}
 		}
 
-		if (err && session->actively_recording()) {
+		if (err && _session.actively_recording()) {
 			/* stop the transport and try to catch as much possible
 			   captured state as we can.
 			*/
-			session->request_stop ();
+			_session.request_stop ();
 		}
 
 		if (i != dsl->end()) {
@@ -304,15 +304,15 @@ Butler::thread_work ()
 		if (compute_io) {
 			// there are no apparent users for this calculation?
 			end = get_microseconds();
-			if(end-begin > 0) {
-			_write_data_rate = (float) bytes / (float) (end - begin);
+			if (end - begin > 0) {
+				_write_data_rate = (float) bytes / (float) (end - begin);
 			} else {
-			_write_data_rate = 0; // Well, infinity would be better
+				_write_data_rate = 0; // Well, infinity would be better
 			}
 		}
 
 		if (!disk_work_outstanding) {
-			session->refresh_disk_space ();
+			_session.refresh_disk_space ();
 		}
 
 
diff --git a/libs/ardour/control_protocol_manager.cc b/libs/ardour/control_protocol_manager.cc
index d15283c85c..47f8d5bf98 100644
--- a/libs/ardour/control_protocol_manager.cc
+++ b/libs/ardour/control_protocol_manager.cc
@@ -39,7 +39,6 @@ ControlProtocolManager* ControlProtocolManager::_instance = 0;
 const string ControlProtocolManager::state_node_name = X_("ControlProtocols");
 
 ControlProtocolManager::ControlProtocolManager ()
-	: _session (0)
 {
 
 }
@@ -63,36 +62,42 @@ ControlProtocolManager::~ControlProtocolManager()
 }
 
 void
-ControlProtocolManager::set_session (Session& s)
+ControlProtocolManager::set_session (Session* s)
 {
-	_session = &s;
-	_session->GoingAway.connect (sigc::mem_fun (*this, &ControlProtocolManager::drop_session));
+	SessionHandlePtr::set_session (s);
 
-	for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
-		if ((*i)->requested || (*i)->mandatory) {
-			instantiate (**i);
-			(*i)->requested = false;
+	if (_session) {
+		Glib::Mutex::Lock lm (protocols_lock);
 
-			if ((*i)->protocol && (*i)->state) {
-				(*i)->protocol->set_state (*(*i)->state, Stateful::loading_state_version);
+		for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
+			if ((*i)->requested || (*i)->mandatory) {
+				instantiate (**i);
+				(*i)->requested = false;
+				
+				if ((*i)->protocol && (*i)->state) {
+					(*i)->protocol->set_state (*(*i)->state, Stateful::loading_state_version);
+				}
 			}
 		}
 	}
 }
 
 void
-ControlProtocolManager::drop_session ()
+ControlProtocolManager::session_going_away()
 {
-	_session = 0;
+	SessionHandlePtr::session_going_away ();
 
 	{
 		Glib::Mutex::Lock lm (protocols_lock);
+
 		for (list<ControlProtocol*>::iterator p = control_protocols.begin(); p != control_protocols.end(); ++p) {
 			delete *p;
 		}
+
 		control_protocols.clear ();
 
 		for (list<ControlProtocolInfo*>::iterator p = control_protocol_info.begin(); p != control_protocol_info.end(); ++p) {
+			// mark existing protocols as requested
 			// otherwise the ControlProtocol instances are not recreated in set_session
 			if ((*p)->protocol) {
 				(*p)->requested = true;
@@ -263,7 +268,7 @@ ControlProtocolManager::get_descriptor (string path)
 }
 
 void
-ControlProtocolManager::foreach_known_protocol (sigc::slot<void,const ControlProtocolInfo*> method)
+ControlProtocolManager::foreach_known_protocol (boost::function<void(const ControlProtocolInfo*)> method)
 {
 	for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
 		method (*i);
diff --git a/libs/ardour/coreaudiosource.cc b/libs/ardour/coreaudiosource.cc
index 55e81ae9e0..bbb0d8ca89 100644
--- a/libs/ardour/coreaudiosource.cc
+++ b/libs/ardour/coreaudiosource.cc
@@ -90,7 +90,7 @@ CoreAudioSource::init_cafile ()
 
 CoreAudioSource::~CoreAudioSource ()
 {
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 }
 
 int
diff --git a/libs/ardour/crossfade.cc b/libs/ardour/crossfade.cc
index 7bbad9a1d1..75f2bae587 100644
--- a/libs/ardour/crossfade.cc
+++ b/libs/ardour/crossfade.cc
@@ -17,7 +17,6 @@
 
 */
 
-#include <sigc++/bind.h>
 
 #include "pbd/stacktrace.h"
 
@@ -192,7 +191,6 @@ Crossfade::Crossfade (boost::shared_ptr<Crossfade> orig, boost::shared_ptr<Audio
 
 Crossfade::~Crossfade ()
 {
-	notify_callbacks ();
 }
 
 void
diff --git a/libs/ardour/delivery.cc b/libs/ardour/delivery.cc
index 07489687c1..7f159a441c 100644
--- a/libs/ardour/delivery.cc
+++ b/libs/ardour/delivery.cc
@@ -42,9 +42,9 @@ using namespace std;
 using namespace PBD;
 using namespace ARDOUR;
 
-sigc::signal<void,nframes_t> Delivery::CycleStart;
-sigc::signal<int>            Delivery::PannersLegal;
-bool                         Delivery::panners_legal = false;
+boost::signals2::signal<void(nframes_t)> Delivery::CycleStart;
+boost::signals2::signal<int()>           Delivery::PannersLegal;
+bool                                     Delivery::panners_legal = false;
 
 /* deliver to an existing IO object */
 
@@ -64,10 +64,10 @@ Delivery::Delivery (Session& s, boost::shared_ptr<IO> io, boost::shared_ptr<Mute
 	_display_to_user = false;
 
 	if (_output) {
-		_output->changed.connect (sigc::mem_fun (*this, &Delivery::output_changed));
+		scoped_connect (_output->changed, boost::bind (&Delivery::output_changed, this, _1, _2));
 	}
 
-	CycleStart.connect (sigc::mem_fun (*this, &Delivery::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&Delivery::cycle_start, this, _1));
 }
 
 /* deliver to a new IO object */
@@ -88,10 +88,10 @@ Delivery::Delivery (Session& s, boost::shared_ptr<MuteMaster> mm, const string&
 	_display_to_user = false;
 
 	if (_output) {
-		_output->changed.connect (sigc::mem_fun (*this, &Delivery::output_changed));
+		scoped_connect (_output->changed, boost::bind (&Delivery::output_changed, this, _1, _2));
 	}
 
-	CycleStart.connect (sigc::mem_fun (*this, &Delivery::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&Delivery::cycle_start, this, _1));
 }
 
 /* deliver to a new IO object, reconstruct from XML */
@@ -116,10 +116,10 @@ Delivery::Delivery (Session& s, boost::shared_ptr<MuteMaster> mm, const XMLNode&
 	}
 
 	if (_output) {
-		_output->changed.connect (sigc::mem_fun (*this, &Delivery::output_changed));
+		scoped_connect (_output->changed, boost::bind (&Delivery::output_changed, this, _1, _2));
 	}
 
-	CycleStart.connect (sigc::mem_fun (*this, &Delivery::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&Delivery::cycle_start, this, _1));
 }
 
 /* deliver to an existing IO object, reconstruct from XML */
@@ -144,10 +144,10 @@ Delivery::Delivery (Session& s, boost::shared_ptr<IO> out, boost::shared_ptr<Mut
 	}
 
 	if (_output) {
-		_output->changed.connect (sigc::mem_fun (*this, &Delivery::output_changed));
+		scoped_connect (_output->changed, boost::bind (&Delivery::output_changed, this, _1, _2));
 	}
 
-	CycleStart.connect (sigc::mem_fun (*this, &Delivery::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&Delivery::cycle_start, this, _1));
 }
 
 std::string
@@ -419,7 +419,7 @@ Delivery::reset_panner ()
 		}
 	} else {
 		panner_legal_c.disconnect ();
-		panner_legal_c = PannersLegal.connect (sigc::mem_fun (*this, &Delivery::panners_became_legal));
+		panner_legal_c = PannersLegal.connect (boost::bind (&Delivery::panners_became_legal, this));
 	}
 }
 
@@ -465,7 +465,7 @@ int
 Delivery::reset_panners ()
 {
 	panners_legal = true;
-	return PannersLegal ();
+	return *PannersLegal ();
 }
 
 
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index ee279c601d..f9e8202ebc 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -31,7 +31,6 @@
 #include <sys/stat.h>
 #include <sys/mman.h>
 
-#include <sigc++/bind.h>
 
 #include "pbd/error.h"
 #include "pbd/basename.h"
@@ -69,8 +68,8 @@ using namespace PBD;
  */
 ARDOUR::nframes_t Diskstream::disk_io_chunk_frames = 1024 * 256;
 
-sigc::signal<void>                Diskstream::DiskOverrun;
-sigc::signal<void>                Diskstream::DiskUnderrun;
+boost::signals2::signal<void()>                Diskstream::DiskOverrun;
+boost::signals2::signal<void()>                Diskstream::DiskUnderrun;
 
 Diskstream::Diskstream (Session &sess, const string &name, Flag flag)
 	: SessionObject(sess, name)
@@ -143,13 +142,13 @@ Diskstream::set_route (Route& r)
 	_io = _route->input();
 
 	ic_connection.disconnect();
-	ic_connection = _io->changed.connect (sigc::mem_fun (*this, &Diskstream::handle_input_change));
+	ic_connection = _io->changed.connect (boost::bind (&Diskstream::handle_input_change, this, _1, _2));
 
 	input_change_pending = ConfigurationChanged;
 	non_realtime_input_change ();
 	set_align_style_from_io ();
 
-	_route->GoingAway.connect (sigc::mem_fun (*this, &Diskstream::route_going_away));
+	scoped_connect (_route->GoingAway, boost::bind (&Diskstream::route_going_away, this));
 }
 
 void
@@ -327,9 +326,7 @@ Diskstream::use_playlist (boost::shared_ptr<Playlist> playlist)
 			return 0;
 		}
 
-		plmod_connection.disconnect ();
-		plgone_connection.disconnect ();
-		plregion_connection.disconnect ();
+		playlist_connections.drop_connections ();
 
 		if (_playlist) {
 			_playlist->release();
@@ -342,9 +339,9 @@ Diskstream::use_playlist (boost::shared_ptr<Playlist> playlist)
 			reset_write_sources (false);
 		}
 
-		plmod_connection = _playlist->Modified.connect (sigc::mem_fun (*this, &Diskstream::playlist_modified));
-		plgone_connection = _playlist->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Diskstream::playlist_deleted), boost::weak_ptr<Playlist>(_playlist)));
-		plregion_connection = _playlist->RangesMoved.connect (sigc::mem_fun (*this, &Diskstream::playlist_ranges_moved));
+		playlist_connections.add_connection (_playlist->Modified.connect (boost::bind (&Diskstream::playlist_modified, this)));
+		playlist_connections.add_connection (_playlist->GoingAway.connect (boost::bind (&Diskstream::playlist_deleted, this, boost::weak_ptr<Playlist>(_playlist))));
+		playlist_connections.add_connection (_playlist->RangesMoved.connect (boost::bind (&Diskstream::playlist_ranges_moved, this, _1)));
 	}
 
 	/* don't do this if we've already asked for it *or* if we are setting up
@@ -457,12 +454,11 @@ Diskstream::playlist_ranges_moved (list< Evoral::RangeMove<nframes_t> > const &
 	}
 
 	/* move processor automation */
-	_route->foreach_processor (sigc::bind (sigc::mem_fun (*this, &Diskstream::move_processor_automation), movements_frames));
+	_route->foreach_processor (boost::bind (&Diskstream::move_processor_automation, this, _1, movements_frames));
 }
 
 void
-Diskstream::move_processor_automation (boost::weak_ptr<Processor> p,
-				       list< Evoral::RangeMove<nframes_t> > const & movements_frames)
+Diskstream::move_processor_automation (boost::weak_ptr<Processor> p, list< Evoral::RangeMove<nframes_t> > const & movements_frames)
 {
 	boost::shared_ptr<Processor> processor (p.lock ());
 	if (!processor) {
diff --git a/libs/ardour/element_importer.cc b/libs/ardour/element_importer.cc
index c02b841ea7..3e7c2c9a91 100644
--- a/libs/ardour/element_importer.cc
+++ b/libs/ardour/element_importer.cc
@@ -32,8 +32,8 @@ using namespace std;
 using namespace PBD;
 using namespace ARDOUR;
 
-sigc::signal <std::pair<bool, string>, string, string> ElementImporter::Rename;
-sigc::signal <bool, string> ElementImporter::Prompt;
+boost::signals2::signal <std::pair<bool, string> (string, string)> ElementImporter::Rename;
+boost::signals2::signal <bool (string)> ElementImporter::Prompt;
 
 ElementImporter::ElementImporter (XMLTree const & source, ARDOUR::Session & session) :
   source (source),
diff --git a/libs/ardour/export_channel.cc b/libs/ardour/export_channel.cc
index 583dc9a843..3006fbc3ee 100644
--- a/libs/ardour/export_channel.cc
+++ b/libs/ardour/export_channel.cc
@@ -108,7 +108,7 @@ RegionExportChannelFactory::RegionExportChannelFactory (Session * session, Audio
 		throw ExportFailed ("Unhandled type in ExportChannelFactory constructor");
 	}
 
-	session->ProcessExport.connect (sigc::hide (sigc::mem_fun (*this, &RegionExportChannelFactory::new_cycle_started)));
+	export_connection = session->ProcessExport.connect (boost::bind (&RegionExportChannelFactory::new_cycle_started, this, _1));
 
 	buffers.set_count (ChanCount (DataType::AUDIO, n_channels));
 	buffers.ensure_buffers (DataType::AUDIO, n_channels, frames_per_cycle);
diff --git a/libs/ardour/export_format_manager.cc b/libs/ardour/export_format_manager.cc
index 908ae6f8a8..f26f0635d8 100644
--- a/libs/ardour/export_format_manager.cc
+++ b/libs/ardour/export_format_manager.cc
@@ -211,13 +211,13 @@ void
 ExportFormatManager::add_compatibility (CompatPtr ptr)
 {
 	compatibilities.push_back (ptr);
-	ptr->SelectChanged.connect (sigc::bind (sigc::mem_fun (*this, &ExportFormatManager::change_compatibility_selection), WeakCompatPtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&ExportFormatManager::change_compatibility_selection, this, _1, WeakCompatPtr (ptr)));
 }
 
 void
 ExportFormatManager::add_quality (QualityPtr ptr)
 {
-	ptr->SelectChanged.connect (sigc::bind (sigc::mem_fun (*this, &ExportFormatManager::change_quality_selection), WeakQualityPtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&ExportFormatManager::change_quality_selection, this, _1, WeakQualityPtr (ptr)));
 	qualities.push_back (ptr);
 }
 
@@ -225,7 +225,7 @@ void
 ExportFormatManager::add_format (FormatPtr ptr)
 {
 	formats.push_back (ptr);
-	ptr->SelectChanged.connect (sigc::bind (sigc::mem_fun (*this, &ExportFormatManager::change_format_selection), WeakFormatPtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&ExportFormatManager::change_format_selection, this, _1, WeakFormatPtr (ptr)));
 	universal_set = universal_set->get_union (*ptr);
 
 	/* Encoding options */
@@ -233,15 +233,15 @@ ExportFormatManager::add_format (FormatPtr ptr)
 	boost::shared_ptr<HasSampleFormat> hsf;
 
 	if (hsf = boost::dynamic_pointer_cast<HasSampleFormat> (ptr)) {
-		hsf->SampleFormatSelectChanged.connect (sigc::mem_fun (*this, &ExportFormatManager::change_sample_format_selection));
-		hsf->DitherTypeSelectChanged.connect (sigc::mem_fun (*this, &ExportFormatManager::change_dither_type_selection));
+		scoped_connect (hsf->SampleFormatSelectChanged, boost::bind (&ExportFormatManager::change_sample_format_selection, this, _1, _2));
+		scoped_connect (hsf->DitherTypeSelectChanged, boost::bind (&ExportFormatManager::change_dither_type_selection, this, _1, _2));
 	}
 }
 
 void
 ExportFormatManager::add_sample_rate (SampleRatePtr ptr)
 {
-	ptr->SelectChanged.connect (sigc::bind (sigc::mem_fun (*this, &ExportFormatManager::change_sample_rate_selection), WeakSampleRatePtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&ExportFormatManager::change_sample_rate_selection, this, _1, WeakSampleRatePtr (ptr)));
 	sample_rates.push_back (ptr);
 }
 
diff --git a/libs/ardour/export_formats.cc b/libs/ardour/export_formats.cc
index 362076876e..b7637f3c07 100644
--- a/libs/ardour/export_formats.cc
+++ b/libs/ardour/export_formats.cc
@@ -59,9 +59,10 @@ HasSampleFormat::add_sample_format (ExportFormatBase::SampleFormat format)
 
 	SampleFormatPtr ptr (new SampleFormatState (format, get_sample_format_name (format)));
 	sample_format_states.push_back (ptr);
-	ptr->SelectChanged.connect (sigc::bind (SampleFormatSelectChanged.make_slot(), WeakSampleFormatPtr (ptr)));
-	ptr->SelectChanged.connect (sigc::mem_fun (*this, &HasSampleFormat::update_sample_format_selection));
-	ptr->CompatibleChanged.connect (sigc::bind (SampleFormatCompatibleChanged.make_slot(), WeakSampleFormatPtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&HasSampleFormat::update_sample_format_selection, this, _1));
+	// BOOST SIGNALS how to connect one signal to another
+	// scoped_connect (ptr->SelectChanged, boost::bind (SampleFormatSelectChanged, _1, WeakSampleFormatPtr (ptr));
+	// scoped_connect (ptr->CompatibleChanged, boost::bind (SampleFormatCompatibleChanged, _1, WeakSampleFormatPtr (ptr));
 }
 
 void
@@ -69,9 +70,10 @@ HasSampleFormat::add_dither_type (ExportFormatBase::DitherType type, Glib::ustri
 {
 	DitherTypePtr ptr (new DitherTypeState (type, name));
 	dither_type_states.push_back (ptr);
-	ptr->SelectChanged.connect (sigc::bind (DitherTypeSelectChanged.make_slot(), WeakDitherTypePtr (ptr)));
-	ptr->SelectChanged.connect (sigc::mem_fun (*this, &HasSampleFormat::update_dither_type_selection));
-	ptr->CompatibleChanged.connect (sigc::bind (DitherTypeCompatibleChanged.make_slot(), WeakDitherTypePtr (ptr)));
+	scoped_connect (ptr->SelectChanged, boost::bind (&HasSampleFormat::update_dither_type_selection, this, _1));
+	// BOOST SIGNALS how to connect one signal to another
+	// scoped_connect (ptr->SelectChanged, boost::bind (DitherTypeSelectChanged, _1, WeakDitherTypePtr (ptr));
+	// scoped_connect (ptr->CompatibleChanged, boost::bind (DitherTypeCompatibleChanged, _1, WeakDitherTypePtr (ptr));
 }
 
 HasSampleFormat::SampleFormatPtr
diff --git a/libs/ardour/export_handler.cc b/libs/ardour/export_handler.cc
index 0c7a2e8d48..7bf231acd2 100644
--- a/libs/ardour/export_handler.cc
+++ b/libs/ardour/export_handler.cc
@@ -98,15 +98,15 @@ ExportElementFactory::add_filename_copy (FilenamePtr other)
 
 /*** ExportHandler ***/
 
-ExportHandler::ExportHandler (Session & session) :
-  ExportElementFactory (session),
-  session (session),
-  export_status (session.get_export_status ()),
-  realtime (false)
+ExportHandler::ExportHandler (Session & session) 
+	: ExportElementFactory (session)
+	, session (session)
+	, export_status (session.get_export_status ())
+	, realtime (false)
 {
 	processor.reset (new ExportProcessor (session));
 
-	files_written_connection = ExportProcessor::WritingFile.connect (sigc::mem_fun (files_written, &std::list<Glib::ustring>::push_back));
+	files_written_connection = ExportProcessor::WritingFile.connect (boost::bind (&ExportHandler::add_file, this, _1));
 }
 
 ExportHandler::~ExportHandler ()
@@ -121,6 +121,12 @@ ExportHandler::~ExportHandler ()
 	files_written_connection.disconnect();
 }
 
+void
+ExportHandler::add_file (const Glib::ustring& str)
+{
+	files_written.push_back (str);
+}
+
 bool
 ExportHandler::add_export_config (TimespanPtr timespan, ChannelConfigPtr channel_config, FormatPtr format, FilenamePtr filename)
 {
@@ -162,7 +168,7 @@ ExportHandler::do_export (bool rt)
 
 	realtime = rt;
 
-	session.ExportReadFinished.connect (sigc::mem_fun (*this, &ExportHandler::finish_timespan));
+	export_read_finished_connection = session.ExportReadFinished.connect (boost::bind (&ExportHandler::finish_timespan, this));
 	start_timespan ();
 }
 
@@ -499,7 +505,7 @@ ExportHandler::start_timespan ()
 
 	/* connect stuff and start export */
 
-	current_timespan->process_connection = session.ProcessExport.connect (sigc::mem_fun (*current_timespan, &ExportTimespan::process));
+	current_timespan->process_connection = session.ProcessExport.connect (boost::bind (&ExportTimespan::process, current_timespan, _1));
 	session.start_audio_export (current_timespan->get_start(), realtime);
 }
 
@@ -538,6 +544,7 @@ void
 ExportHandler::timespan_thread_finished ()
 {
 	channel_config_connection.disconnect();
+	export_read_finished_connection.disconnect ();
 
 	if (current_map_it != timespan_bounds.second) {
 
@@ -559,7 +566,7 @@ ExportHandler::timespan_thread_finished ()
 			cc = current_map_it->second.channel_config;
 		}
 
-		channel_config_connection = cc->FilesWritten.connect (sigc::mem_fun (*this, &ExportHandler::timespan_thread_finished));
+		channel_config_connection = cc->FilesWritten.connect (boost::bind (&ExportHandler::timespan_thread_finished, this));
 		++current_map_it;
 
 	} else { /* All files are written from current timespan, reset timespan and start new */
diff --git a/libs/ardour/export_processor.cc b/libs/ardour/export_processor.cc
index d36ef9f18a..7d04e8f8d6 100644
--- a/libs/ardour/export_processor.cc
+++ b/libs/ardour/export_processor.cc
@@ -38,7 +38,7 @@ using namespace PBD;
 namespace ARDOUR
 {
 
-sigc::signal<void, Glib::ustring> ExportProcessor::WritingFile;
+boost::signals2::signal<void (const Glib::ustring&)> ExportProcessor::WritingFile;
 
 ExportProcessor::ExportProcessor (Session & session) :
   session (session),
diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index 9953524c34..e3e37a7107 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -109,7 +109,7 @@ apply_gain_to_buffer_t  ARDOUR::apply_gain_to_buffer = 0;
 mix_buffers_with_gain_t ARDOUR::mix_buffers_with_gain = 0;
 mix_buffers_no_gain_t   ARDOUR::mix_buffers_no_gain = 0;
 
-sigc::signal<void,std::string> ARDOUR::BootMessage;
+boost::signals2::signal<void(std::string)> ARDOUR::BootMessage;
 
 void ARDOUR::setup_enum_writer ();
 
diff --git a/libs/ardour/internal_return.cc b/libs/ardour/internal_return.cc
index 41c29f43f1..ccee62c988 100644
--- a/libs/ardour/internal_return.cc
+++ b/libs/ardour/internal_return.cc
@@ -27,20 +27,20 @@
 using namespace std;
 using namespace ARDOUR;
 
-sigc::signal<void,nframes_t> InternalReturn::CycleStart;
+boost::signals2::signal<void(nframes_t)> InternalReturn::CycleStart;
 
 InternalReturn::InternalReturn (Session& s)
 	: Return (s, true)
 	, user_count (0)
 {
-	CycleStart.connect (sigc::mem_fun (*this, &InternalReturn::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&InternalReturn::cycle_start, this, _1));
 }
 
 InternalReturn::InternalReturn (Session& s, const XMLNode& node)
 	: Return (s, node, true)
 	, user_count (0)
 {
-	CycleStart.connect (sigc::mem_fun (*this, &InternalReturn::cycle_start));
+	scoped_connect (CycleStart, boost::bind (&InternalReturn::cycle_start, this, _1));
 }
 
 void
diff --git a/libs/ardour/internal_send.cc b/libs/ardour/internal_send.cc
index e10857a2a9..d6489f8f49 100644
--- a/libs/ardour/internal_send.cc
+++ b/libs/ardour/internal_send.cc
@@ -43,8 +43,8 @@ InternalSend::InternalSend (Session& s, boost::shared_ptr<MuteMaster> mm, boost:
 
 	set_name (sendto->name());
 
-	_send_to->GoingAway.connect (sigc::mem_fun (*this, &InternalSend::send_to_going_away));
-	_send_to->NameChanged.connect (sigc::mem_fun (*this, &InternalSend::send_to_name_changed));
+	scoped_connect (_send_to->GoingAway, boost::bind (&InternalSend::send_to_going_away, this));
+	scoped_connect (_send_to->NameChanged, boost::bind (&InternalSend::send_to_name_changed, this));
 }
 
 InternalSend::InternalSend (Session& s, boost::shared_ptr<MuteMaster> mm, const XMLNode& node)
@@ -187,7 +187,7 @@ InternalSend::set_our_state (const XMLNode& node, int version)
 		*/
 
 		if (!IO::connecting_legal) {
-			connect_c = IO::ConnectingLegal.connect (sigc::mem_fun (*this, &InternalSend::connect_when_legal));
+			connect_c = IO::ConnectingLegal.connect (boost::bind (&InternalSend::connect_when_legal, this));
 		} else {
 			connect_when_legal ();
 		}
diff --git a/libs/ardour/io.cc b/libs/ardour/io.cc
index d8d7ec88a5..b9fd9ccbc6 100644
--- a/libs/ardour/io.cc
+++ b/libs/ardour/io.cc
@@ -22,7 +22,6 @@
 #include <locale.h>
 #include <errno.h>
 
-#include <sigc++/bind.h>
 
 #include <glibmm.h>
 #include <glibmm/thread.h>
@@ -68,8 +67,8 @@ using namespace PBD;
 
 const string                 IO::state_node_name = "IO";
 bool                         IO::connecting_legal = false;
-sigc::signal<int>            IO::ConnectingLegal;
-sigc::signal<void,ChanCount> IO::PortCountChanged;
+boost::signals2::signal<int()>            IO::ConnectingLegal;
+boost::signals2::signal<void(ChanCount)> IO::PortCountChanged;
 
 /** @param default_type The type of port that will be created by ensure_io
  * and friends if no type is explicitly requested (to avoid breakage).
@@ -124,13 +123,13 @@ IO::check_bundles_connected ()
 }
 
 void
-IO::check_bundles (std::vector<UserBundleInfo>& list, const PortSet& ports)
+IO::check_bundles (std::vector<UserBundleInfo*>& list, const PortSet& ports)
 {
-	std::vector<UserBundleInfo> new_list;
+	std::vector<UserBundleInfo*> new_list;
 
-	for (std::vector<UserBundleInfo>::iterator i = list.begin(); i != list.end(); ++i) {
+	for (std::vector<UserBundleInfo*>::iterator i = list.begin(); i != list.end(); ++i) {
 
-		uint32_t const N = i->bundle->nchannels ();
+		uint32_t const N = (*i)->bundle->nchannels ();
 
 		if (_ports.num_ports (default_type()) < N) {
 			continue;
@@ -140,7 +139,7 @@ IO::check_bundles (std::vector<UserBundleInfo>& list, const PortSet& ports)
 
 		for (uint32_t j = 0; j < N; ++j) {
 			/* Every port on bundle channel j must be connected to our input j */
-			Bundle::PortList const pl = i->bundle->channel_ports (j);
+			Bundle::PortList const pl = (*i)->bundle->channel_ports (j);
 			for (uint32_t k = 0; k < pl.size(); ++k) {
 				if (ports.port(j)->connected_to (pl[k]) == false) {
 					ok = false;
@@ -156,7 +155,7 @@ IO::check_bundles (std::vector<UserBundleInfo>& list, const PortSet& ports)
 		if (ok) {
 			new_list.push_back (*i);
 		} else {
-			i->changed.disconnect ();
+			delete *i;
 		}
 	}
 
@@ -475,9 +474,9 @@ IO::state (bool /*full_state*/)
 	node->add_property ("direction", enum_2_string (_direction));
 	node->add_property ("default-type", _default_type.to_string());
 
-	for (std::vector<UserBundleInfo>::iterator i = _bundles_connected.begin(); i != _bundles_connected.end(); ++i) {
+	for (std::vector<UserBundleInfo*>::iterator i = _bundles_connected.begin(); i != _bundles_connected.end(); ++i) {
 		XMLNode* n = new XMLNode ("Bundle");
-		n->add_property ("name", i->bundle->name ());
+		n->add_property ("name", (*i)->bundle->name ());
 		node->add_child_nocopy (*n);
 	}
 
@@ -567,7 +566,7 @@ IO::set_state (const XMLNode& node, int version)
 		pending_state_node = new XMLNode (node);
 		pending_state_node_version = version;
 		pending_state_node_in = false;
-		connection_legal_c = ConnectingLegal.connect (sigc::mem_fun (*this, &IO::connecting_became_legal));
+		connection_legal_c = ConnectingLegal.connect (boost::bind (&IO::connecting_became_legal, this));
 	}
 
 
@@ -620,7 +619,7 @@ IO::set_state_2X (const XMLNode& node, int version, bool in)
 		pending_state_node = new XMLNode (node);
 		pending_state_node_version = version;
 		pending_state_node_in = in;
-		connection_legal_c = ConnectingLegal.connect (sigc::mem_fun (*this, &IO::connecting_became_legal));
+		connection_legal_c = ConnectingLegal.connect (boost::bind (&IO::connecting_became_legal, this));
 	}
 
 	return 0;
@@ -1164,14 +1163,14 @@ IO::connect_ports_to_bundle (boost::shared_ptr<Bundle> c, void* src)
 		if (ub) {
 
 			/* See if we already know about this one */
-			std::vector<UserBundleInfo>::iterator i = _bundles_connected.begin();
-			while (i != _bundles_connected.end() && i->bundle != ub) {
+			std::vector<UserBundleInfo*>::iterator i = _bundles_connected.begin();
+			while (i != _bundles_connected.end() && (*i)->bundle != ub) {
 				++i;
 			}
 
 			if (i == _bundles_connected.end()) {
 				/* We don't, so make a note */
-				_bundles_connected.push_back (UserBundleInfo (this, ub));
+				_bundles_connected.push_back (new UserBundleInfo (this, ub));
 			}
 		}
 	}
@@ -1194,12 +1193,13 @@ IO::disconnect_ports_from_bundle (boost::shared_ptr<Bundle> c, void* src)
 		boost::shared_ptr<UserBundle> ub = boost::dynamic_pointer_cast<UserBundle> (c);
 		if (ub) {
 
-			std::vector<UserBundleInfo>::iterator i = _bundles_connected.begin();
-			while (i != _bundles_connected.end() && i->bundle != ub) {
+			std::vector<UserBundleInfo*>::iterator i = _bundles_connected.begin();
+			while (i != _bundles_connected.end() && (*i)->bundle != ub) {
 				++i;
 			}
 
 			if (i != _bundles_connected.end()) {
+				delete *i;
 				_bundles_connected.erase (i);
 			}
 		}
@@ -1221,7 +1221,7 @@ int
 IO::enable_connecting ()
 {
 	connecting_legal = true;
-	return ConnectingLegal ();
+	return *ConnectingLegal ();
 }
 
 void
@@ -1362,8 +1362,8 @@ IO::bundles_connected ()
 	BundleList bundles;
 
 	/* User bundles */
-	for (std::vector<UserBundleInfo>::iterator i = _bundles_connected.begin(); i != _bundles_connected.end(); ++i) {
-		bundles.push_back (i->bundle);
+	for (std::vector<UserBundleInfo*>::iterator i = _bundles_connected.begin(); i != _bundles_connected.end(); ++i) {
+		bundles.push_back ((*i)->bundle);
 	}
 
 	/* Session bundles */
@@ -1399,9 +1399,7 @@ IO::bundles_connected ()
 IO::UserBundleInfo::UserBundleInfo (IO* io, boost::shared_ptr<UserBundle> b)
 {
 	bundle = b;
-	changed = b->Changed.connect (
-		sigc::mem_fun (*io, &IO::bundle_changed)
-		);
+	changed = b->Changed.connect (boost::bind (&IO::bundle_changed, io, _1));
 }
 
 std::string
diff --git a/libs/ardour/io_processor.cc b/libs/ardour/io_processor.cc
index 6bdac9fe19..91247d5082 100644
--- a/libs/ardour/io_processor.cc
+++ b/libs/ardour/io_processor.cc
@@ -24,7 +24,6 @@
 #include <unistd.h>
 #include <sstream>
 
-#include <sigc++/bind.h>
 
 #include "pbd/xml++.h"
 #include "pbd/enumwriter.h"
@@ -89,7 +88,6 @@ IOProcessor::IOProcessor (Session& s, boost::shared_ptr<IO> in, boost::shared_pt
 
 IOProcessor::~IOProcessor ()
 {
-	notify_callbacks ();
 }
 
 void
diff --git a/libs/ardour/ladspa_plugin.cc b/libs/ardour/ladspa_plugin.cc
index a242a76c31..b0d64ad41b 100644
--- a/libs/ardour/ladspa_plugin.cc
+++ b/libs/ardour/ladspa_plugin.cc
@@ -144,7 +144,7 @@ LadspaPlugin::~LadspaPlugin ()
 	deactivate ();
 	cleanup ();
 
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 
 	/* XXX who should close a plugin? */
 
diff --git a/libs/ardour/location.cc b/libs/ardour/location.cc
index 24e4628c0b..7e3330ecd9 100644
--- a/libs/ardour/location.cc
+++ b/libs/ardour/location.cc
@@ -25,7 +25,6 @@
 #include <ctime>
 #include <list>
 
-#include <sigc++/bind.h>
 
 #include "pbd/stl_delete.h"
 #include "pbd/xml++.h"
diff --git a/libs/ardour/location_importer.cc b/libs/ardour/location_importer.cc
index 6fb9f7b7db..655a8f1a84 100644
--- a/libs/ardour/location_importer.cc
+++ b/libs/ardour/location_importer.cc
@@ -143,7 +143,7 @@ LocationImporter::_prepare_move ()
 	std::pair<bool, string> rename_pair;
 
 	if (location->is_auto_punch()) {
-		rename_pair = Rename (_("The location is the Punch range. It will be imported as a normal range.\nYou may rename the imported location:"), name);
+		rename_pair = *Rename (_("The location is the Punch range. It will be imported as a normal range.\nYou may rename the imported location:"), name);
 		if (!rename_pair.first) {
 			return false;
 		}
@@ -154,7 +154,7 @@ LocationImporter::_prepare_move ()
 	}
 
 	if (location->is_auto_loop()) {
-		rename_pair = Rename (_("The location is a Loop range. It will be imported as a normal range.\nYou may rename the imported location:"), name);
+		rename_pair = *Rename (_("The location is a Loop range. It will be imported as a normal range.\nYou may rename the imported location:"), name);
 		if (!rename_pair.first) { return false; }
 
 		location->set_auto_loop (false, this);
@@ -165,7 +165,7 @@ LocationImporter::_prepare_move ()
 	Locations::LocationList const & locations(session.locations()->list());
 	for (Locations::LocationList::const_iterator it = locations.begin(); it != locations.end(); ++it) {
 		if (!((*it)->name().compare (location->name())) || !handler.check_name (location->name())) {
-			rename_pair = Rename (_("A location with that name already exists.\nYou may rename the imported location:"), name);
+			rename_pair = *Rename (_("A location with that name already exists.\nYou may rename the imported location:"), name);
 			if (!rename_pair.first) { return false; }
 			name = rename_pair.second;
 		}
diff --git a/libs/ardour/lv2_plugin.cc b/libs/ardour/lv2_plugin.cc
index 2090d18e96..6c593a869a 100644
--- a/libs/ardour/lv2_plugin.cc
+++ b/libs/ardour/lv2_plugin.cc
@@ -181,7 +181,7 @@ LV2Plugin::~LV2Plugin ()
 	deactivate ();
 	cleanup ();
 
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 
 	slv2_instance_free(_instance);
 	slv2_value_free(_name);
diff --git a/libs/ardour/meter.cc b/libs/ardour/meter.cc
index 4566ed7e02..4ad0f58580 100644
--- a/libs/ardour/meter.cc
+++ b/libs/ardour/meter.cc
@@ -31,20 +31,20 @@ using namespace std;
 
 using namespace ARDOUR;
 
-sigc::signal<void> Metering::Meter;
+boost::signals2::signal<void()> Metering::Meter;
 Glib::StaticMutex  Metering::m_meter_signal_lock;
 
-sigc::connection
-Metering::connect (sigc::slot<void> the_slot)
+boost::signals2::connection
+Metering::connect (boost::function<void()> f)
 {
 	// SignalProcessor::Meter is emitted from another thread so the
 	// Meter signal must be protected.
 	Glib::Mutex::Lock guard (m_meter_signal_lock);
-	return Meter.connect (the_slot);
+	return Meter.connect (f);
 }
 
 void
-Metering::disconnect (sigc::connection& c)
+Metering::disconnect (boost::signals2::connection& c)
 {
 	Glib::Mutex::Lock guard (m_meter_signal_lock);
 	c.disconnect ();
diff --git a/libs/ardour/midi_clock_slave.cc b/libs/ardour/midi_clock_slave.cc
index e2b83a1e65..12d25ac9ae 100644
--- a/libs/ardour/midi_clock_slave.cc
+++ b/libs/ardour/midi_clock_slave.cc
@@ -43,7 +43,8 @@ using namespace MIDI;
 using namespace PBD;
 
 MIDIClock_Slave::MIDIClock_Slave (Session& s, MIDI::Port& p, int ppqn)
-	: ppqn (ppqn)
+ 	: port_connections (0)
+	, ppqn (ppqn)
 	, bandwidth (30.0 / 60.0) // 1 BpM = 1 / 60 Hz
 {
 	session = (ISlaveSessionProxy *) new SlaveSessionProxy(s);
@@ -53,6 +54,7 @@ MIDIClock_Slave::MIDIClock_Slave (Session& s, MIDI::Port& p, int ppqn)
 
 MIDIClock_Slave::MIDIClock_Slave (ISlaveSessionProxy* session_proxy, int ppqn)
 	: session(session_proxy)
+	, port_connections (0)
 	, ppqn (ppqn)
 	, bandwidth (30.0 / 60.0) // 1 BpM = 1 / 60 Hz
 {
@@ -62,27 +64,27 @@ MIDIClock_Slave::MIDIClock_Slave (ISlaveSessionProxy* session_proxy, int ppqn)
 
 MIDIClock_Slave::~MIDIClock_Slave()
 {
-  delete session;
+	delete session;
+	delete port_connections;
 }
 
 void
 MIDIClock_Slave::rebind (MIDI::Port& p)
 {
-	for (vector<sigc::connection>::iterator i = connections.begin(); i != connections.end(); ++i) {
-		(*i).disconnect ();
-	}
-
+	delete port_connections;
+	port_connections = new ScopedConnectionList;
+	
 	port = &p;
 
-	#ifdef DEBUG_MIDI_CLOCK
-		std::cerr << "MIDIClock_Slave: connecting to port " << port->name() << std::endl;
-	#endif
+#ifdef DEBUG_MIDI_CLOCK
+	std::cerr << "MIDIClock_Slave: connecting to port " << port->name() << std::endl;
+#endif
 
-	connections.push_back (port->input()->timing.connect   (sigc::mem_fun (*this, &MIDIClock_Slave::update_midi_clock)));
-	connections.push_back (port->input()->start.connect    (sigc::mem_fun (*this, &MIDIClock_Slave::start)));
-	connections.push_back (port->input()->contineu.connect (sigc::mem_fun (*this, &MIDIClock_Slave::contineu)));
-	connections.push_back (port->input()->stop.connect     (sigc::mem_fun (*this, &MIDIClock_Slave::stop)));
-	connections.push_back (port->input()->position.connect (sigc::mem_fun (*this, &MIDIClock_Slave::position)));
+	port_connections->add_connection (port->input()->timing.connect (boost::bind (&MIDIClock_Slave::update_midi_clock, this, _1, _2)));
+	port_connections->add_connection (port->input()->start.connect (boost::bind (&MIDIClock_Slave::start, this, _1, _2)));
+	port_connections->add_connection (port->input()->contineu.connect (boost::bind (&MIDIClock_Slave::contineu, this, _1, _2)));
+	port_connections->add_connection (port->input()->stop.connect (boost::bind (&MIDIClock_Slave::stop, this, _1, _2)));
+	port_connections->add_connection (port->input()->position.connect (boost::bind (&MIDIClock_Slave::position, this, _1, _2, 3)));
 }
 
 void
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index f780948d69..6b181b1a27 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -1024,7 +1024,7 @@ MidiDiskstream::transport_stopped (struct tm& /*when*/, time_t /*twhen*/, bool a
 				continue; /* XXX is this OK? */
 			}
 
-			region->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Diskstream::remove_region_from_last_capture), boost::weak_ptr<Region>(region)));
+			scoped_connect (region->GoingAway, boost::bind (&Diskstream::remove_region_from_last_capture, this, boost::weak_ptr<Region>(region)));
 
 			_last_capture_regions.push_back (region);
 
diff --git a/libs/ardour/midi_model.cc b/libs/ardour/midi_model.cc
index 47bc14852c..baa3c2c7c0 100644
--- a/libs/ardour/midi_model.cc
+++ b/libs/ardour/midi_model.cc
@@ -267,7 +267,7 @@ MidiModel::DeltaCommand::set_state (const XMLNode& delta_command, int /*version*
 	if (added_notes) {
 		XMLNodeList notes = added_notes->children();
 		transform(notes.begin(), notes.end(), back_inserter(_added_notes),
-			  sigc::mem_fun(*this, &DeltaCommand::unmarshal_note));
+			  boost::bind (&DeltaCommand::unmarshal_note, this, _1));
 	}
 
 	_removed_notes.clear();
@@ -275,7 +275,7 @@ MidiModel::DeltaCommand::set_state (const XMLNode& delta_command, int /*version*
 	if (removed_notes) {
 		XMLNodeList notes = removed_notes->children();
 		transform(notes.begin(), notes.end(), back_inserter(_removed_notes),
-			  sigc::mem_fun(*this, &DeltaCommand::unmarshal_note));
+			  boost::bind (&DeltaCommand::unmarshal_note, this, _1));
 	}
 
 	return 0;
@@ -288,14 +288,16 @@ MidiModel::DeltaCommand::get_state()
 	delta_command->add_property("midi-source", _model->midi_source()->id().to_s());
 
 	XMLNode* added_notes = delta_command->add_child(ADDED_NOTES_ELEMENT);
-	for_each(_added_notes.begin(), _added_notes.end(), sigc::compose(
-			sigc::mem_fun(*added_notes, &XMLNode::add_child_nocopy),
-			sigc::mem_fun(*this, &DeltaCommand::marshal_note)));
+	for_each(_added_notes.begin(), _added_notes.end(), 
+		 boost::bind(
+			 boost::bind (&XMLNode::add_child_nocopy, *added_notes, _1),
+			 boost::bind (&DeltaCommand::marshal_note, this, _1)));
 
 	XMLNode* removed_notes = delta_command->add_child(REMOVED_NOTES_ELEMENT);
-	for_each(_removed_notes.begin(), _removed_notes.end(), sigc::compose(
-			sigc::mem_fun(*removed_notes, &XMLNode::add_child_nocopy),
-			sigc::mem_fun(*this, &DeltaCommand::marshal_note)));
+	for_each(_removed_notes.begin(), _removed_notes.end(), 
+		 boost::bind (
+			 boost::bind (&XMLNode::add_child_nocopy, *removed_notes, _1),
+			 boost::bind (&DeltaCommand::marshal_note, this, _1)));
 
 	return *delta_command;
 }
@@ -650,9 +652,9 @@ MidiModel::DiffCommand::set_state(const XMLNode& diff_command, int /*version*/)
 
 	if (changed_notes) {
 		XMLNodeList notes = changed_notes->children();
-
 		transform (notes.begin(), notes.end(), back_inserter(_changes),
-			   sigc::mem_fun(*this, &DiffCommand::unmarshal_change));
+			   boost::bind (&DiffCommand::unmarshal_change, this, _1));
+
 	}
 
 	return 0;
@@ -665,9 +667,10 @@ MidiModel::DiffCommand::get_state ()
 	diff_command->add_property("midi-source", _model->midi_source()->id().to_s());
 
 	XMLNode* changes = diff_command->add_child(DIFF_NOTES_ELEMENT);
-	for_each(_changes.begin(), _changes.end(), sigc::compose(
-			 sigc::mem_fun(*changes, &XMLNode::add_child_nocopy),
-			 sigc::mem_fun(*this, &DiffCommand::marshal_change)));
+	for_each(_changes.begin(), _changes.end(), 
+		 boost::bind (
+			 boost::bind (&XMLNode::add_child_nocopy, *changes, _1),
+			 boost::bind (&DiffCommand::marshal_change, this, _1)));
 
 	return *diff_command;
 }
diff --git a/libs/ardour/midi_patch_manager.cc b/libs/ardour/midi_patch_manager.cc
index 307655bff8..a2522fe997 100644
--- a/libs/ardour/midi_patch_manager.cc
+++ b/libs/ardour/midi_patch_manager.cc
@@ -18,7 +18,6 @@
     $Id$
 */
 
-#include <sigc++/sigc++.h>
 #include <boost/shared_ptr.hpp>
 
 #include "pbd/compose.h"
@@ -41,11 +40,9 @@ using namespace PBD::sys;
 MidiPatchManager* MidiPatchManager::_manager = 0;
 
 void
-MidiPatchManager::set_session (Session& s)
+MidiPatchManager::set_session (Session* s)
 {
-	_session = &s;
-	_session->GoingAway.connect (sigc::mem_fun (*this, &MidiPatchManager::drop_session));
-
+	SessionHandlePtr::set_session (s);
 	refresh();
 }
 
@@ -56,6 +53,10 @@ MidiPatchManager::refresh()
 	_master_devices_by_model.clear();
 	_all_models.clear();
 
+	if (!_session) {
+		return;
+	}
+
 	path path_to_patches = _session->session_directory().midi_patch_path();
 
 	if (!exists(path_to_patches)) {
@@ -93,10 +94,8 @@ MidiPatchManager::refresh()
 }
 
 void
-MidiPatchManager::drop_session ()
+MidiPatchManager::session_going_away ()
 {
-	_session = 0;
-	_documents.clear();
-	_master_devices_by_model.clear();
-	_all_models.clear();
+	SessionHandlePtr::session_going_away ();
+	refresh ();
 }
diff --git a/libs/ardour/midi_playlist.cc b/libs/ardour/midi_playlist.cc
index b230f6f6d5..a8e60ec866 100644
--- a/libs/ardour/midi_playlist.cc
+++ b/libs/ardour/midi_playlist.cc
@@ -23,7 +23,6 @@
 #include <iostream>
 
 #include <stdlib.h>
-#include <sigc++/bind.h>
 
 #include "evoral/EventList.hpp"
 
@@ -72,11 +71,9 @@ MidiPlaylist::MidiPlaylist (boost::shared_ptr<const MidiPlaylist> other, nframes
 
 MidiPlaylist::~MidiPlaylist ()
 {
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 
 	/* drop connections to signals */
-
-	notify_callbacks ();
 }
 
 template<typename Time>
diff --git a/libs/ardour/midi_region.cc b/libs/ardour/midi_region.cc
index a722afd399..3b13d4db8d 100644
--- a/libs/ardour/midi_region.cc
+++ b/libs/ardour/midi_region.cc
@@ -24,8 +24,6 @@
 
 #include <set>
 
-#include <sigc++/bind.h>
-#include <sigc++/class_slot.h>
 
 #include <glibmm/thread.h>
 
@@ -54,7 +52,7 @@ MidiRegion::MidiRegion (boost::shared_ptr<MidiSource> src, nframes_t start, nfra
 	: Region (src, start, length, PBD::basename_nosuffix(src->name()), DataType::MIDI, 0,  Region::Flag(Region::DefaultFlags|Region::External))
 {
 	assert(_name.find("/") == string::npos);
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 }
 
 /* Basic MidiRegion constructor (one channel) */
@@ -62,7 +60,7 @@ MidiRegion::MidiRegion (boost::shared_ptr<MidiSource> src, nframes_t start, nfra
 	: Region (src, start, length, name, DataType::MIDI, layer, flags)
 {
 	assert(_name.find("/") == string::npos);
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 }
 
 /* Basic MidiRegion constructor (many channels) */
@@ -70,7 +68,7 @@ MidiRegion::MidiRegion (const SourceList& srcs, nframes_t start, nframes_t lengt
 	: Region (srcs, start, length, name, DataType::MIDI, layer, flags)
 {
 	assert(_name.find("/") == string::npos);
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 }
 
 
@@ -79,14 +77,14 @@ MidiRegion::MidiRegion (boost::shared_ptr<const MidiRegion> other, nframes_t off
 	: Region (other, offset, length, name, layer, flags)
 {
 	assert(_name.find("/") == string::npos);
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 }
 
 MidiRegion::MidiRegion (boost::shared_ptr<const MidiRegion> other)
 	: Region (other)
 {
 	assert(_name.find("/") == string::npos);
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 }
 
 MidiRegion::MidiRegion (boost::shared_ptr<MidiSource> src, const XMLNode& node)
@@ -96,7 +94,7 @@ MidiRegion::MidiRegion (boost::shared_ptr<MidiSource> src, const XMLNode& node)
 		throw failed_constructor();
 	}
 
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 	assert(_name.find("/") == string::npos);
 	assert(_type == DataType::MIDI);
 }
@@ -108,7 +106,7 @@ MidiRegion::MidiRegion (const SourceList& srcs, const XMLNode& node)
 		throw failed_constructor();
 	}
 
-	midi_source(0)->Switched.connect(sigc::mem_fun(this, &MidiRegion::switch_source));
+	scoped_connect (midi_source(0)->Switched, boost::bind (&MidiRegion::switch_source, this, _1));
 	assert(_name.find("/") == string::npos);
 	assert(_type == DataType::MIDI);
 }
diff --git a/libs/ardour/midi_source.cc b/libs/ardour/midi_source.cc
index 2ece2f53ce..14b096c915 100644
--- a/libs/ardour/midi_source.cc
+++ b/libs/ardour/midi_source.cc
@@ -49,7 +49,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,MidiSource *> MidiSource::MidiSourceCreated;
+boost::signals2::signal<void(MidiSource*)> MidiSource::MidiSourceCreated;
 
 MidiSource::MidiSource (Session& s, string name, Source::Flag flags)
 	: Source(s, DataType::MIDI, name, flags)
@@ -260,7 +260,7 @@ MidiSource::session_saved()
 
 		newsrc->flush_midi();
 
-		Switched.emit(newsrc);
+		Switched (newsrc); /* EMIT SIGNAL */
 	}
 }
 
diff --git a/libs/ardour/midi_track.cc b/libs/ardour/midi_track.cc
index ebbe231e62..179d0bb57c 100644
--- a/libs/ardour/midi_track.cc
+++ b/libs/ardour/midi_track.cc
@@ -17,9 +17,6 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 #include "pbd/error.h"
-#include <sigc++/retype.h>
-#include <sigc++/retype_return.h>
-#include <sigc++/bind.h>
 
 #include "pbd/enumwriter.h"
 #include "midi++/events.h"
@@ -233,7 +230,7 @@ MidiTrack::_set_state (const XMLNode& node, int version, bool call_base)
 	pending_state = const_cast<XMLNode*> (&node);
 
 	if (_session.state_of_the_state() & Session::Loading) {
-		_session.StateReady.connect (sigc::mem_fun (*this, &MidiTrack::set_state_part_two));
+		scoped_connect (_session.StateReady, boost::bind (&MidiTrack::set_state_part_two, this));
 	} else {
 		set_state_part_two ();
 	}
diff --git a/libs/ardour/midi_ui.cc b/libs/ardour/midi_ui.cc
index 1bb10d713f..db26ee8e83 100644
--- a/libs/ardour/midi_ui.cc
+++ b/libs/ardour/midi_ui.cc
@@ -18,6 +18,8 @@
 */
 #include <cstdlib>
 
+#include <sigc++/signal.h>
+
 #include "pbd/pthread_utils.h"
 
 #include "midi++/manager.h"
@@ -44,7 +46,7 @@ MidiControlUI::MidiControlUI (Session& s)
 	: AbstractUI<MidiUIRequest> (_("midiui"))
 	, _session (s) 
 {
-	MIDI::Manager::instance()->PortsChanged.connect (sigc::mem_fun (*this, &MidiControlUI::change_midi_ports));
+	rebind_connection = MIDI::Manager::instance()->PortsChanged.connect (boost::bind (&MidiControlUI::change_midi_ports, this));
 }
 
 MidiControlUI::~MidiControlUI ()
@@ -125,7 +127,7 @@ MidiControlUI::reset_ports ()
 		if ((fd = (*i)->selectable ()) >= 0) {
 			Glib::RefPtr<IOSource> psrc = IOSource::create (fd, IO_IN|IO_HUP|IO_ERR);
 
-			psrc->connect (sigc::bind (sigc::mem_fun (*this, &MidiControlUI::midi_input_handler), (*i)));
+			psrc->connect (sigc::bind (sigc::mem_fun (this, &MidiControlUI::midi_input_handler), *i));
 			psrc->attach (_main_loop->get_context());
 
 			// glibmm hack: for now, store only the GSource*
diff --git a/libs/ardour/mtc_slave.cc b/libs/ardour/mtc_slave.cc
index 3e06efa56f..50ef5011ba 100644
--- a/libs/ardour/mtc_slave.cc
+++ b/libs/ardour/mtc_slave.cc
@@ -52,6 +52,7 @@ const int MTC_Slave::frame_tolerance = 2;
 
 MTC_Slave::MTC_Slave (Session& s, MIDI::Port& p)
 	: session (s)
+	, port_connections (0)
 {
 	can_notify_on_unknown_rate = true;
 	did_reset_tc_format = false;
@@ -70,9 +71,12 @@ MTC_Slave::MTC_Slave (Session& s, MIDI::Port& p)
 
 MTC_Slave::~MTC_Slave()
 {
+	delete port_connections;
+
 	if (did_reset_tc_format) {
 		session.config.set_timecode_format (saved_tc_format);
 	}
+
 	delete pic;
 	delete [] speed_accumulator;
 }
@@ -87,15 +91,14 @@ MTC_Slave::give_slave_full_control_over_transport_speed() const
 void
 MTC_Slave::rebind (MIDI::Port& p)
 {
-	for (vector<sigc::connection>::iterator i = connections.begin(); i != connections.end(); ++i) {
-		(*i).disconnect ();
-	}
-
+	delete port_connections;
+	port_connections = new ScopedConnectionList;
+	
 	port = &p;
-
-	connections.push_back (port->input()->mtc_time.connect (sigc::mem_fun (*this, &MTC_Slave::update_mtc_time)));
-	connections.push_back (port->input()->mtc_qtr.connect (sigc::mem_fun (*this, &MTC_Slave::update_mtc_qtr)));
-	connections.push_back (port->input()->mtc_status.connect (sigc::mem_fun (*this, &MTC_Slave::update_mtc_status)));
+	
+	port_connections->add_connection (port->input()->mtc_time.connect ( boost::bind (&MTC_Slave::update_mtc_time, this, _1, _2, _3)));
+	port_connections->add_connection (port->input()->mtc_qtr.connect (boost::bind (&MTC_Slave::update_mtc_qtr, this, _1, _2, _3)));
+	port_connections->add_connection (port->input()->mtc_status.connect (boost::bind (&MTC_Slave::update_mtc_status, this, _1)));
 }
 
 void
diff --git a/libs/ardour/named_selection.cc b/libs/ardour/named_selection.cc
index 5353d1e824..81e9f9df8a 100644
--- a/libs/ardour/named_selection.cc
+++ b/libs/ardour/named_selection.cc
@@ -32,7 +32,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,NamedSelection*> NamedSelection::NamedSelectionCreated;
+boost::signals2::signal<void(NamedSelection*)> NamedSelection::NamedSelectionCreated;
 
 typedef std::list<boost::shared_ptr<Playlist> > PlaylistList;
 
@@ -102,7 +102,7 @@ NamedSelection::~NamedSelection ()
 {
 	for (PlaylistList::iterator i = playlists.begin(); i != playlists.end(); ++i) {
 		(*i)->release ();
-		(*i)->GoingAway ();
+		(*i)->drop_references ();
 	}
 }
 
diff --git a/libs/ardour/playlist.cc b/libs/ardour/playlist.cc
index 29beb7c6b7..b93e2b311a 100644
--- a/libs/ardour/playlist.cc
+++ b/libs/ardour/playlist.cc
@@ -25,7 +25,6 @@
 #include <string>
 #include <climits>
 
-#include <sigc++/bind.h>
 
 #include "pbd/failed_constructor.h"
 #include "pbd/stl_delete.h"
@@ -116,7 +115,9 @@ Playlist::Playlist (Session& sess, const XMLNode& node, DataType type, bool hide
 }
 
 Playlist::Playlist (boost::shared_ptr<const Playlist> other, string namestr, bool hide)
-	: SessionObject(other->_session, namestr), _type(other->_type), _orig_diskstream_id(other->_orig_diskstream_id)
+	: SessionObject(other->_session, namestr)
+	, _type(other->_type)
+	, _orig_diskstream_id(other->_orig_diskstream_id)
 {
 	init (hide);
 
@@ -148,7 +149,9 @@ Playlist::Playlist (boost::shared_ptr<const Playlist> other, string namestr, boo
 }
 
 Playlist::Playlist (boost::shared_ptr<const Playlist> other, nframes_t start, nframes_t cnt, string str, bool hide)
-	: SessionObject(other->_session, str), _type(other->_type), _orig_diskstream_id(other->_orig_diskstream_id)
+	: SessionObject(other->_session, str)
+	, _type(other->_type)
+	, _orig_diskstream_id(other->_orig_diskstream_id)
 {
 	RegionLock rlock2 (const_cast<Playlist*> (other.get()));
 
@@ -267,12 +270,13 @@ Playlist::init (bool hide)
 	freeze_length = 0;
 	_explicit_relayering = false;
 
-	Modified.connect (sigc::mem_fun (*this, &Playlist::mark_session_dirty));
+	scoped_connect (Modified, boost::bind (&Playlist::mark_session_dirty, this));
 }
 
 Playlist::~Playlist ()
 {
 	DEBUG_TRACE (DEBUG::Destruction, string_compose ("Playlist %1 destructor\n", _name));
+
 	{
 		RegionLock rl (this);
 
@@ -601,10 +605,8 @@ Playlist::add_region_internal (boost::shared_ptr<Region> region, nframes_t posit
 		}
 	}
 
-	region_state_changed_connections.push_back (
-		region->StateChanged.connect (sigc::bind (sigc::mem_fun (this, &Playlist::region_changed_proxy),
-							  boost::weak_ptr<Region> (region)))
-		);
+	region_state_changed_connections.add_connection 
+		(region->StateChanged.connect (boost::bind (&Playlist::region_changed_proxy, this, _1, boost::weak_ptr<Region> (region))));
 
 	return true;
 }
@@ -1318,7 +1320,6 @@ Playlist::region_changed_proxy (Change what_changed, boost::weak_ptr<Region> wea
 		return;
 	}
 
-
 	/* this makes a virtual call to the right kind of playlist ... */
 
 	region_changed (what_changed, region);
@@ -1369,13 +1370,7 @@ Playlist::clear (bool with_signals)
 	{
 		RegionLock rl (this);
 
-		for (
-			std::list<sigc::connection>::iterator i = region_state_changed_connections.begin ();
-			i != region_state_changed_connections.end ();
-			++i
-		) {
-			i->disconnect ();
-		}
+		region_state_changed_connections.drop_connections ();
 
 		for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
 			pending_removes.insert (*i);
@@ -2493,7 +2488,7 @@ Playlist::update_after_tempo_map_change ()
 }
 
 void
-Playlist::foreach_region (sigc::slot<void, boost::shared_ptr<Region> > s)
+Playlist::foreach_region (boost::function<void(boost::shared_ptr<Region>)> s)
 {
 	RegionLock rl (this, false);
 	for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
diff --git a/libs/ardour/playlist_factory.cc b/libs/ardour/playlist_factory.cc
index 554c36df17..cfcec40d1b 100644
--- a/libs/ardour/playlist_factory.cc
+++ b/libs/ardour/playlist_factory.cc
@@ -31,7 +31,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,boost::shared_ptr<Playlist>, bool> PlaylistFactory::PlaylistCreated;
+boost::signals2::signal<void(boost::shared_ptr<Playlist>, bool)> PlaylistFactory::PlaylistCreated;
 
 boost::shared_ptr<Playlist>
 PlaylistFactory::create (Session& s, const XMLNode& node, bool hidden, bool unused)
diff --git a/libs/ardour/plugin_insert.cc b/libs/ardour/plugin_insert.cc
index f41d6bbc25..c2bf7f3562 100644
--- a/libs/ardour/plugin_insert.cc
+++ b/libs/ardour/plugin_insert.cc
@@ -23,7 +23,6 @@
 
 #include <string>
 
-#include <sigc++/bind.h>
 
 #include "pbd/failed_constructor.h"
 #include "pbd/xml++.h"
@@ -131,7 +130,7 @@ PluginInsert::set_count (uint32_t num)
 
 PluginInsert::~PluginInsert ()
 {
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 }
 
 void
diff --git a/libs/ardour/port_insert.cc b/libs/ardour/port_insert.cc
index eccd5f29f9..044230e1f7 100644
--- a/libs/ardour/port_insert.cc
+++ b/libs/ardour/port_insert.cc
@@ -19,7 +19,6 @@
 
 #include <string>
 
-#include <sigc++/bind.h>
 
 #include "pbd/failed_constructor.h"
 #include "pbd/xml++.h"
@@ -62,7 +61,7 @@ PortInsert::PortInsert (Session& s, boost::shared_ptr<MuteMaster> mm, const XMLN
 
 PortInsert::~PortInsert ()
 {
-	GoingAway ();
+	drop_references ();
 }
 
 void
diff --git a/libs/ardour/processor.cc b/libs/ardour/processor.cc
index 3bc9db024b..54701ae8d4 100644
--- a/libs/ardour/processor.cc
+++ b/libs/ardour/processor.cc
@@ -23,7 +23,6 @@
 
 #include <string>
 
-#include <sigc++/bind.h>
 
 #include "pbd/failed_constructor.h"
 #include "pbd/enumwriter.h"
@@ -57,7 +56,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,Processor*> Processor::ProcessorCreated;
+boost::signals2::signal<void(Processor*)> Processor::ProcessorCreated;
 
 // Always saved as Processor, but may be IOProcessor or Send in legacy sessions
 const string Processor::state_node_name = "Processor";
@@ -269,7 +268,7 @@ Processor::configure_io (ChanCount in, ChanCount out)
 	_configured_output = out;
 	_configured = true;
 
-	ConfigurationChanged.emit (in, out);
+	ConfigurationChanged (in, out); /* EMIT SIGNAL */
 
 	return true;
 }
diff --git a/libs/ardour/region.cc b/libs/ardour/region.cc
index 2c4d8004cf..4fcb7de3ca 100644
--- a/libs/ardour/region.cc
+++ b/libs/ardour/region.cc
@@ -23,8 +23,6 @@
 #include <algorithm>
 #include <sstream>
 
-#include <sigc++/bind.h>
-#include <sigc++/class_slot.h>
 
 #include <glibmm/thread.h>
 #include "pbd/xml++.h"
@@ -56,7 +54,7 @@ Change Region::LockChanged       = ARDOUR::new_change ();
 Change Region::LayerChanged      = ARDOUR::new_change ();
 Change Region::HiddenChanged     = ARDOUR::new_change ();
 
-sigc::signal<void,boost::shared_ptr<ARDOUR::Region> > Region::RegionPropertyChanged;
+boost::signals2::signal<void(boost::shared_ptr<ARDOUR::Region>)> Region::RegionPropertyChanged;
 
 /* derived-from-derived constructor (no sources in constructor) */
 Region::Region (Session& s, nframes_t start, nframes_t length, const string& name, DataType type, layer_t layer, Region::Flag flags)
@@ -111,7 +109,7 @@ Region::Region (boost::shared_ptr<Source> src, nframes_t start, nframes_t length
 	_sources.push_back (src);
 	_master_sources.push_back (src);
 
-	src->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Region::source_deleted), src));
+	scoped_connect (src->GoingAway, boost::bind (&Region::source_deleted, this, boost::weak_ptr<Source>(src)));
 
 	assert(_sources.size() > 0);
 	_positional_lock_style = AudioTime;
@@ -340,7 +338,6 @@ Region::Region (boost::shared_ptr<Source> src, const XMLNode& node)
 Region::~Region ()
 {
 	DEBUG_TRACE (DEBUG::Destruction, string_compose ("Region %1 destructor @ %2\n", _name, this));
-	notify_callbacks ();
 	drop_references ();
 }
 
@@ -1416,9 +1413,10 @@ Region::region_list_equivalent (boost::shared_ptr<const Region> other) const
 }
 
 void
-Region::source_deleted (boost::shared_ptr<Source>)
+Region::source_deleted (boost::weak_ptr<Source>)
 {
 	_sources.clear ();
+	cerr << "Send drop ref signal from region " << ' ' << this << endl;
 	drop_references ();
 }
 
@@ -1588,14 +1586,14 @@ Region::use_sources (SourceList const & s)
 
 	for (SourceList::const_iterator i = s.begin (); i != s.end(); ++i) {
 		_sources.push_back (*i);
-		(*i)->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Region::source_deleted), *i));
+		scoped_connect ((*i)->GoingAway, boost::bind (&Region::source_deleted, this, boost::weak_ptr<Source>(*i)));
 		unique_srcs.insert (*i);
 	}
 
 	for (SourceList::const_iterator i = s.begin (); i != s.end(); ++i) {
 		_master_sources.push_back (*i);
 		if (unique_srcs.find (*i) == unique_srcs.end()) {
-			(*i)->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Region::source_deleted), *i));
+			scoped_connect ((*i)->GoingAway, boost::bind (&Region::source_deleted, this, boost::weak_ptr<Source>(*i)));
 		}
 	}
 }
diff --git a/libs/ardour/region_factory.cc b/libs/ardour/region_factory.cc
index 91cc2dbe2a..ff4b9d5270 100644
--- a/libs/ardour/region_factory.cc
+++ b/libs/ardour/region_factory.cc
@@ -34,7 +34,7 @@
 using namespace ARDOUR;
 using namespace PBD;
 
-sigc::signal<void,boost::shared_ptr<Region> > RegionFactory::CheckNewRegion;
+boost::signals2::signal<void(boost::shared_ptr<Region>)> RegionFactory::CheckNewRegion;
 
 boost::shared_ptr<Region>
 RegionFactory::create (boost::shared_ptr<Region> region, nframes_t start,
diff --git a/libs/ardour/return.cc b/libs/ardour/return.cc
index 82d1cf6ff2..991c6ae7d1 100644
--- a/libs/ardour/return.cc
+++ b/libs/ardour/return.cc
@@ -67,7 +67,7 @@ Return::Return (Session& s, const XMLNode& node, bool internal)
 
 Return::~Return ()
 {
-	GoingAway ();
+	drop_references ();
 }
 
 XMLNode&
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 3390245828..154c5fd0a0 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -22,7 +22,6 @@
 #include <cassert>
 #include <algorithm>
 
-#include <sigc++/bind.h>
 #include "pbd/xml++.h"
 #include "pbd/enumwriter.h"
 #include "pbd/memento_command.h"
@@ -64,7 +63,7 @@ using namespace ARDOUR;
 using namespace PBD;
 
 uint32_t Route::order_key_cnt = 0;
-sigc::signal<void, string const &> Route::SyncOrderKeys;
+boost::signals2::signal<void(string const&)> Route::SyncOrderKeys;
 
 Route::Route (Session& sess, string name, Flag flg, DataType default_type)
 	: SessionObject (sess, name)
@@ -94,7 +93,7 @@ Route::Route (Session& sess, string name, Flag flg, DataType default_type)
 
 	/* now that we have _meter, its safe to connect to this */
 
-	_meter_connection = Metering::connect (sigc::mem_fun (*this, &Route::meter));
+	scoped_connect (Metering::Meter, (boost::bind (&Route::meter, this)));
 }
 
 Route::Route (Session& sess, const XMLNode& node, DataType default_type)
@@ -110,7 +109,7 @@ Route::Route (Session& sess, const XMLNode& node, DataType default_type)
 
 	/* now that we have _meter, its safe to connect to this */
 
-	_meter_connection = Metering::connect (sigc::mem_fun (*this, &Route::meter));
+	scoped_connect (Metering::Meter, (boost::bind (&Route::meter, this)));
 }
 
 void
@@ -148,8 +147,8 @@ Route::init ()
 	_input.reset (new IO (_session, _name, IO::Input, _default_type));
 	_output.reset (new IO (_session, _name, IO::Output, _default_type));
 
-	_input->changed.connect (sigc::mem_fun (this, &Route::input_change_handler));
-	_output->changed.connect (sigc::mem_fun (this, &Route::output_change_handler));
+	scoped_connect (_input->changed, boost::bind (&Route::input_change_handler, this, _1, _2));
+	scoped_connect (_output->changed, boost::bind (&Route::output_change_handler, this, _1, _2));
 
 	/* add amp processor  */
 
@@ -160,7 +159,6 @@ Route::init ()
 Route::~Route ()
 {
 	DEBUG_TRACE (DEBUG::Destruction, string_compose ("route %1 destructor\n", _name));
-	Metering::disconnect (_meter_connection);
 
 	/* don't use clear_processors here, as it depends on the session which may
 	   be half-destroyed by now */
@@ -794,7 +792,7 @@ Route::add_processor (boost::shared_ptr<Processor> processor, ProcessorList::ite
 			// XXX: do we want to emit the signal here ? change call order.
 			processor->activate ();
 		}
-		processor->ActiveChanged.connect (sigc::bind (sigc::mem_fun (_session, &Session::update_latency_compensation), false, false));
+		scoped_connect (processor->ActiveChanged, boost::bind (&Session::update_latency_compensation, &_session, false, false));
 
 		_output->set_user_latency (0);
 	}
@@ -1049,7 +1047,7 @@ Route::add_processors (const ProcessorList& others, ProcessorList::iterator iter
 				return -1;
 			}
 
-			(*i)->ActiveChanged.connect (sigc::bind (sigc::mem_fun (_session, &Session::update_latency_compensation), false, false));
+			scoped_connect ((*i)->ActiveChanged, boost::bind (&Session::update_latency_compensation, &_session, false, false));
 		}
 
 		_output->set_user_latency (0);
diff --git a/libs/ardour/route_group.cc b/libs/ardour/route_group.cc
index 3d98c61548..82953be0f8 100644
--- a/libs/ardour/route_group.cc
+++ b/libs/ardour/route_group.cc
@@ -22,7 +22,6 @@
 
 #include <algorithm>
 
-#include <sigc++/bind.h>
 
 #include "pbd/error.h"
 #include "pbd/enumwriter.h"
@@ -77,7 +76,7 @@ RouteGroup::add (boost::shared_ptr<Route> r)
 	routes->push_back (r);
 
 	r->join_route_group (this);
-	r->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &RouteGroup::remove_when_going_away), boost::weak_ptr<Route> (r)));
+	scoped_connect (r->GoingAway, boost::bind (&RouteGroup::remove_when_going_away, this, boost::weak_ptr<Route> (r)));
 	
 	_session.set_dirty ();
 	changed (); /* EMIT SIGNAL */
diff --git a/libs/ardour/send.cc b/libs/ardour/send.cc
index 6117b09be2..1bb03642d0 100644
--- a/libs/ardour/send.cc
+++ b/libs/ardour/send.cc
@@ -64,7 +64,7 @@ Send::Send (Session& s, boost::shared_ptr<MuteMaster> mm, const XMLNode& node, i
 
 Send::~Send ()
 {
-	GoingAway ();
+	drop_references ();
 }
 
 void
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index fbe8edfa80..d8e3b2843c 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -28,8 +28,6 @@
 #include <unistd.h>
 #include <limits.h>
 
-#include <sigc++/bind.h>
-#include <sigc++/retype.h>
 
 #include <glibmm/thread.h>
 #include <glibmm/miscutils.h>
@@ -105,17 +103,17 @@ using boost::weak_ptr;
 
 bool Session::_disable_all_loaded_plugins = false;
 
-sigc::signal<void,std::string> Session::Dialog;
-sigc::signal<int> Session::AskAboutPendingState;
-sigc::signal<int,nframes_t,nframes_t> Session::AskAboutSampleRateMismatch;
-sigc::signal<void> Session::SendFeedback;
+boost::signals2::signal<void(std::string)> Session::Dialog;
+boost::signals2::signal<int()> Session::AskAboutPendingState;
+boost::signals2::signal<int(nframes_t,nframes_t)> Session::AskAboutSampleRateMismatch;
+boost::signals2::signal<void()> Session::SendFeedback;
 
-sigc::signal<void> Session::TimecodeOffsetChanged;
-sigc::signal<void> Session::StartTimeChanged;
-sigc::signal<void> Session::EndTimeChanged;
-sigc::signal<void> Session::AutoBindingOn;
-sigc::signal<void> Session::AutoBindingOff;
-sigc::signal<void, std::string, std::string> Session::Exported;
+boost::signals2::signal<void()> Session::TimecodeOffsetChanged;
+boost::signals2::signal<void()> Session::StartTimeChanged;
+boost::signals2::signal<void()> Session::EndTimeChanged;
+boost::signals2::signal<void()> Session::AutoBindingOn;
+boost::signals2::signal<void()> Session::AutoBindingOff;
+boost::signals2::signal<void(std::string, std::string)> Session::Exported;
 
 static void clean_up_session_event (SessionEvent* ev) { delete ev; }
 const SessionEvent::RTeventCallback Session::rt_cleanup (clean_up_session_event);
@@ -138,7 +136,7 @@ Session::Session (AudioEngine &eng,
 	  _midi_clock_port (default_midi_clock_port),
 	  _session_dir (new SessionDirectory(fullpath)),
 	  state_tree (0),
-	  _butler (new Butler (this)),
+	  _butler (new Butler (*this)),
 	  _post_transport_work (0),
 	  _send_timecode_update (false),
 	  diskstreams (new DiskstreamList),
@@ -191,8 +189,8 @@ Session::Session (AudioEngine &eng,
 
 	_state_of_the_state = StateOfTheState (_state_of_the_state & ~Dirty);
 
-	Config->ParameterChanged.connect (sigc::bind (sigc::mem_fun (*this, &Session::config_changed), false));
-	config.ParameterChanged.connect (sigc::bind (sigc::mem_fun (*this, &Session::config_changed), true));
+	scoped_connect (Config->ParameterChanged, boost::bind (&Session::config_changed, this, _1, false));
+	scoped_connect (config.ParameterChanged, boost::bind (&Session::config_changed, this, _1, true));
 
 	if (was_dirty) {
 		DirtyChanged (); /* EMIT SIGNAL */
@@ -223,7 +221,7 @@ Session::Session (AudioEngine &eng,
 	  _midi_clock_port (default_midi_clock_port),
 	  _session_dir ( new SessionDirectory(fullpath)),
 	  state_tree (0),
-	  _butler (new Butler (this)),
+	  _butler (new Butler (*this)),
 	  _post_transport_work (0),
 	  _send_timecode_update (false),
 	  diskstreams (new DiskstreamList),
@@ -280,7 +278,9 @@ Session::Session (AudioEngine &eng,
 
 		if (master_out_channels) {
 			ChanCount count(DataType::AUDIO, master_out_channels);
-			shared_ptr<Route> r (new Route (*this, _("master"), Route::MasterOut, DataType::AUDIO));
+			Route* rt = new Route (*this, _("master"), Route::MasterOut, DataType::AUDIO);
+			boost_debug_shared_ptr_mark_interesting (rt, typeid (rt).name());
+			shared_ptr<Route> r (rt);
 			r->input()->ensure_io (count, false, this);
 			r->output()->ensure_io (count, false, this);
 			r->set_remote_control_id (control_id);
@@ -293,7 +293,9 @@ Session::Session (AudioEngine &eng,
 
 		if (control_out_channels) {
 			ChanCount count(DataType::AUDIO, control_out_channels);
-			shared_ptr<Route> r (new Route (*this, _("monitor"), Route::ControlOut, DataType::AUDIO));
+			Route* rt = new Route (*this, _("monitor"), Route::ControlOut, DataType::AUDIO);
+			boost_debug_shared_ptr_mark_interesting (rt, typeid (rt).name());
+			shared_ptr<Route> r (rt);
 			r->input()->ensure_io (count, false, this);
 			r->output()->ensure_io (count, false, this);
 			r->set_remote_control_id (control_id++);
@@ -324,7 +326,7 @@ Session::Session (AudioEngine &eng,
 
 	_state_of_the_state = StateOfTheState (_state_of_the_state & ~Dirty);
 
-	Config->ParameterChanged.connect (sigc::bind (sigc::mem_fun (*this, &Session::config_changed), false));
+	scoped_connect (Config->ParameterChanged, boost::bind (&Session::config_changed, this, _1, false));
 }
 
 Session::~Session ()
@@ -347,12 +349,6 @@ Session::destroy ()
 
 	_engine.remove_session ();
 
-	GoingAway (); /* EMIT SIGNAL */
-
-	/* do this */
-
-	notify_callbacks ();
-
 	/* clear history so that no references to objects are held any more */
 
 	_history.clear ();
@@ -391,7 +387,7 @@ Session::destroy ()
 	
 	AudioDiskstream::free_working_buffers();
 
-	Route::SyncOrderKeys.clear();
+	// BOOST::SIGNALS: Route::SyncOrderKeys.clear();
 
 	DEBUG_TRACE (DEBUG::Destruction, "delete named selections\n");
 	for (NamedSelectionList::iterator i = named_selections.begin(); i != named_selections.end(); ) {
@@ -410,6 +406,8 @@ Session::destroy ()
 
 		tmp = i;
 		++tmp;
+
+		boost::shared_ptr<Region> keep (i->second);
 		
 		DEBUG_TRACE(DEBUG::Destruction, string_compose ("Dropping for region %1 (%2); pre-ref = %3\n", i->second->name(), i->second.get(), i->second.use_count()));
 		i->second->drop_references ();
@@ -479,6 +477,10 @@ Session::destroy ()
 	/* not strictly necessary, but doing it here allows the shared_ptr debugging to work */
 	playlists.reset ();
 
+	/* tell everyone who is still standing that we're about to die */
+
+	drop_references ();
+
 	boost_debug_list_ptrs ();
 
 	DEBUG_TRACE (DEBUG::Destruction, "Session::destroy() done\n");
@@ -522,7 +524,7 @@ Session::when_engine_running ()
 
 	/* every time we reconnect, recompute worst case output latencies */
 
-	_engine.Running.connect (sigc::mem_fun (*this, &Session::set_worst_io_latencies));
+	scoped_connect (_engine.Running, boost::bind (&Session::set_worst_io_latencies, this));
 
 	if (synced_to_jack()) {
 		_engine.transport_stop ();
@@ -876,7 +878,7 @@ Session::diskstream_playlist_changed (boost::weak_ptr<Diskstream> wp)
 	boost::shared_ptr<Playlist> playlist;
 
 	if ((playlist = dstream->playlist()) != 0) {
-		playlist->LengthChanged.connect (sigc::mem_fun (this, &Session::playlist_length_changed));
+		scoped_connect (playlist->LengthChanged, boost::bind (&Session::playlist_length_changed, this));
 	}
 
 	/* see comment in playlist_length_changed () */
@@ -992,9 +994,7 @@ Session::set_auto_punch_location (Location* location)
 	Location* existing;
 
 	if ((existing = _locations.auto_punch_location()) != 0 && existing != location) {
-		auto_punch_start_changed_connection.disconnect();
-		auto_punch_end_changed_connection.disconnect();
-		auto_punch_changed_connection.disconnect();
+		punch_connections.drop_connections();
 		existing->set_auto_punch (false, this);
 		remove_event (existing->start(), SessionEvent::PunchIn);
 		clear_events (SessionEvent::PunchOut);
@@ -1012,17 +1012,14 @@ Session::set_auto_punch_location (Location* location)
 		return;
 	}
 
-	auto_punch_start_changed_connection.disconnect();
-	auto_punch_end_changed_connection.disconnect();
-	auto_punch_changed_connection.disconnect();
+	punch_connections.drop_connections ();
 
-	auto_punch_start_changed_connection = location->start_changed.connect (sigc::mem_fun (this, &Session::auto_punch_start_changed));
-	auto_punch_end_changed_connection = location->end_changed.connect (sigc::mem_fun (this, &Session::auto_punch_end_changed));
-	auto_punch_changed_connection = location->changed.connect (sigc::mem_fun (this, &Session::auto_punch_changed));
+	punch_connections.add_connection (location->start_changed.connect (boost::bind (&Session::auto_punch_start_changed, this, _1)));
+	punch_connections.add_connection (location->end_changed.connect (boost::bind (&Session::auto_punch_end_changed, this, _1)));
+	punch_connections.add_connection (location->changed.connect (boost::bind (&Session::auto_punch_changed, this, _1)));
 
 	location->set_auto_punch (true, this);
 
-
 	auto_punch_changed (location);
 
 	auto_punch_location_changed (location);
@@ -1034,9 +1031,7 @@ Session::set_auto_loop_location (Location* location)
 	Location* existing;
 
 	if ((existing = _locations.auto_loop_location()) != 0 && existing != location) {
-		auto_loop_start_changed_connection.disconnect();
-		auto_loop_end_changed_connection.disconnect();
-		auto_loop_changed_connection.disconnect();
+		loop_connections.drop_connections ();
 		existing->set_auto_loop (false, this);
 		remove_event (existing->end(), SessionEvent::AutoLoop);
 		auto_loop_location_changed (0);
@@ -1055,16 +1050,11 @@ Session::set_auto_loop_location (Location* location)
 
 	last_loopend = location->end();
 
-	auto_loop_start_changed_connection.disconnect();
-	auto_loop_end_changed_connection.disconnect();
-	auto_loop_changed_connection.disconnect();
+	loop_connections.drop_connections ();
 
-	auto_loop_start_changed_connection = location->start_changed.connect (
-			sigc::mem_fun (this, &Session::auto_loop_changed));
-	auto_loop_end_changed_connection = location->end_changed.connect (
-			sigc::mem_fun (this, &Session::auto_loop_changed));
-	auto_loop_changed_connection = location->changed.connect (
-			sigc::mem_fun (this, &Session::auto_loop_changed));
+	loop_connections.add_connection (location->start_changed.connect (boost::bind (&Session::auto_loop_changed, this, _1)));
+	loop_connections.add_connection (location->end_changed.connect (boost::bind (&Session::auto_loop_changed, this, _1)));
+	loop_connections.add_connection (location->changed.connect (boost::bind (&Session::auto_loop_changed, this, _1)));
 
 	location->set_auto_loop (true, this);
 
@@ -1658,7 +1648,7 @@ Session::new_midi_track (TrackMode mode, RouteGroup* route_group, uint32_t how_m
 				route_group->add (track);
 			}
 
-			track->DiskstreamChanged.connect (sigc::mem_fun (this, &Session::resort_routes));
+			scoped_connect (track->DiskstreamChanged, boost::bind (&Session::resort_routes, this));
 			//track->set_remote_control_id (control_id);
 
 			new_routes.push_back (track);
@@ -1771,7 +1761,7 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
 
 		try {
 			AudioTrack* at = new AudioTrack (*this, track_name, Route::Flag (0), mode);
-			// boost_debug_shared_ptr_mark_interesting (at, typeid (at).name());
+			boost_debug_shared_ptr_mark_interesting (at, typeid (at).name());
 			track = boost::shared_ptr<AudioTrack>(at);
 
 			if (track->input()->ensure_io (ChanCount(DataType::AUDIO, input_channels), false, this)) {
@@ -1833,7 +1823,7 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
 
 			track->audio_diskstream()->non_realtime_input_change();
 
-			track->DiskstreamChanged.connect (sigc::mem_fun (this, &Session::resort_routes));
+			scoped_connect (track->DiskstreamChanged, boost::bind (&Session::resort_routes, this));
 			track->set_remote_control_id (control_id);
 			++control_id;
 
@@ -1961,7 +1951,9 @@ Session::new_audio_route (bool aux, int input_channels, int output_channels, Rou
 		} while (bus_id < (UINT_MAX-1));
 
 		try {
-			shared_ptr<Route> bus (new Route (*this, bus_name, Route::Flag(0), DataType::AUDIO));
+			Route* rt = new Route (*this, bus_name, Route::Flag(0), DataType::AUDIO);
+			boost_debug_shared_ptr_mark_interesting (rt, typeid (rt).name());
+			shared_ptr<Route> bus (rt);
 
 			if (bus->input()->ensure_io (ChanCount(DataType::AUDIO, input_channels), false, this)) {
 				error << string_compose (_("cannot configure %1 in/%2 out configuration for new audio track"),
@@ -2158,12 +2150,12 @@ Session::add_routes (RouteList& new_routes, bool save)
 
 		boost::weak_ptr<Route> wpr (*x);
 
-		(*x)->listen_changed.connect (sigc::bind (sigc::mem_fun (*this, &Session::route_listen_changed), wpr));
-		(*x)->solo_changed.connect (sigc::bind (sigc::mem_fun (*this, &Session::route_solo_changed), wpr));
-		(*x)->mute_changed.connect (sigc::mem_fun (*this, &Session::route_mute_changed));
-		(*x)->output()->changed.connect (sigc::mem_fun (*this, &Session::set_worst_io_latencies_x));
-		(*x)->processors_changed.connect (sigc::mem_fun (*this, &Session::route_processors_changed));
-		(*x)->route_group_changed.connect (sigc::mem_fun (*this, &Session::route_group_changed));
+		scoped_connect ((*x)->listen_changed, boost::bind (&Session::route_listen_changed, this, _1, wpr));
+		scoped_connect ((*x)->solo_changed, boost::bind (&Session::route_solo_changed, this, _1, wpr));
+		scoped_connect ((*x)->mute_changed, boost::bind (&Session::route_mute_changed, this, _1));
+		scoped_connect ((*x)->output()->changed, boost::bind (&Session::set_worst_io_latencies_x, this, _1, _2));
+		scoped_connect ((*x)->processors_changed, boost::bind (&Session::route_processors_changed, this, _1));
+		scoped_connect ((*x)->route_group_changed, boost::bind (&Session::route_group_changed, this));
 
 		if ((*x)->is_master()) {
 			_master_out = (*x);
@@ -2303,11 +2295,11 @@ Session::add_diskstream (boost::shared_ptr<Diskstream> dstream)
 		/* writer goes out of scope, copies ds back to main */
 	}
 
-	dstream->PlaylistChanged.connect (sigc::bind (sigc::mem_fun (*this, &Session::diskstream_playlist_changed), boost::weak_ptr<Diskstream> (dstream)));
+	scoped_connect (dstream->PlaylistChanged, boost::bind (&Session::diskstream_playlist_changed, this, boost::weak_ptr<Diskstream> (dstream)));
 	/* this will connect to future changes, and check the current length */
 	diskstream_playlist_changed (boost::weak_ptr<Diskstream> (dstream));
 
-	dstream->RecordEnableChanged.connect (sigc::mem_fun (*this, &Session::update_have_rec_enabled_diskstream));
+	scoped_connect (dstream->RecordEnableChanged, boost::bind (&Session::update_have_rec_enabled_diskstream, this));
 
 	dstream->prepare ();
 
@@ -2821,8 +2813,8 @@ Session::add_regions (vector<boost::shared_ptr<Region> >& new_regions)
 				}
 			}
 
-			region->StateChanged.connect (sigc::bind (sigc::mem_fun (*this, &Session::region_changed), boost::weak_ptr<Region>(region)));
-			region->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Session::remove_region), boost::weak_ptr<Region>(region)));
+			scoped_connect (region->StateChanged, boost::bind (&Session::region_changed, this, _1, boost::weak_ptr<Region>(region)));
+			scoped_connect (region->GoingAway, boost::bind (&Session::remove_region, this, boost::weak_ptr<Region>(region)));
 
 			update_region_name_map (region);
 		}
@@ -3010,7 +3002,7 @@ Session::add_source (boost::shared_ptr<Source> source)
 	}
 
 	if (result.second) {
-		source->GoingAway.connect (sigc::bind (sigc::mem_fun (this, &Session::remove_source), boost::weak_ptr<Source> (source)));
+		scoped_connect (source->GoingAway, boost::bind (&Session::remove_source, this, boost::weak_ptr<Source> (source)));
 		set_dirty();
 	}
 
@@ -3401,7 +3393,7 @@ Session::add_playlist (boost::shared_ptr<Playlist> playlist, bool unused)
 
 	bool existing = playlists->add (playlist);
 	if (!existing) {
-		playlist->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Session::remove_playlist), boost::weak_ptr<Playlist>(playlist)));
+		scoped_connect (playlist->GoingAway, boost::bind (&Session::remove_playlist, this, boost::weak_ptr<Playlist>(playlist)));
 	}
 
 	if (unused) {
@@ -3492,8 +3484,8 @@ Session::remove_empty_sounds ()
 	TapeFileMatcher tape_file_matcher;
 
 	remove_if (audio_filenames.begin(), audio_filenames.end(),
-			sigc::mem_fun (tape_file_matcher, &TapeFileMatcher::matches));
-
+		   boost::bind (&TapeFileMatcher::matches, &tape_file_matcher, _1));
+	
 	for (vector<string>::iterator i = audio_filenames.begin(); i != audio_filenames.end(); ++i) {
 
 		sys::path audio_file_path (_session_dir->sound_path());
@@ -3575,7 +3567,7 @@ Session::graph_reordered ()
 void
 Session::add_processor (Processor* processor)
 {
-	processor->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &Session::remove_processor), processor));
+	scoped_connect (processor->GoingAway, boost::bind (&Session::remove_processor, this, processor));
 	set_dirty();
 }
 
diff --git a/libs/ardour/session_command.cc b/libs/ardour/session_command.cc
index 4d733264fb..828af69901 100644
--- a/libs/ardour/session_command.cc
+++ b/libs/ardour/session_command.cc
@@ -43,7 +43,7 @@ using namespace ARDOUR;
 
 #include "i18n.h"
 
-void Session::register_with_memento_command_factory(PBD::ID id, PBD::StatefulThingWithGoingAway *ptr)
+void Session::register_with_memento_command_factory(PBD::ID id, PBD::StatefulDestructible *ptr)
 {
     registry[id] = ptr;
 }
@@ -114,8 +114,8 @@ Session::memento_command_factory(XMLNode *n)
 		if (i != automation_lists.end()) {
 		    return new MementoCommand<AutomationList>(*i->second, before, after);
 		}
-    } else if (registry.count(id)) { // For Editor and AutomationLine which are off-limits here
-	    return new MementoCommand<PBD::StatefulThingWithGoingAway>(*registry[id], before, after);
+    } else if (registry.count(id)) { // For Editor and AutomationLine which are off-limits herea
+	    return new MementoCommand<PBD::StatefulDestructible>(*registry[id], before, after);
     }
 
     /* we failed */
diff --git a/libs/ardour/session_export.cc b/libs/ardour/session_export.cc
index da18ceb3cb..8b56271e42 100644
--- a/libs/ardour/session_export.cc
+++ b/libs/ardour/session_export.cc
@@ -17,7 +17,6 @@
 
 */
 
-#include <sigc++/bind.h>
 
 #include "pbd/error.h"
 #include <glibmm/thread.h>
@@ -92,8 +91,8 @@ Session::pre_export ()
 
 	_exporting = true;
 	export_status->running = true;
-	export_status->Aborting.connect (sigc::hide_return (sigc::mem_fun (*this, &Session::stop_audio_export)));
-	export_status->Finished.connect (sigc::hide_return (sigc::mem_fun (*this, &Session::finalize_audio_export)));
+	scoped_connect (export_status->Aborting, boost::bind (&Session::stop_audio_export, this));
+	scoped_connect (export_status->Finished, boost::bind (&Session::finalize_audio_export, this));
 
 	return 0;
 }
@@ -151,7 +150,7 @@ Session::start_audio_export (nframes_t position, bool realtime)
 		last_process_function = process_function;
 		process_function = &Session::process_export;
 	} else {
-		export_freewheel_connection = _engine.Freewheel.connect (sigc::mem_fun (*this, &Session::process_export_fw));
+		export_freewheel_connection = _engine.Freewheel.connect (boost::bind (&Session::process_export_fw, this, _1));
 		return _engine.freewheel (true);
 	}
 
@@ -180,7 +179,7 @@ Session::process_export (nframes_t nframes)
 
 		process_without_events (nframes);
 
-		/* handle export */
+		/* handle export - XXX what about error handling? */
 
 		ProcessExport (nframes);
 
@@ -236,8 +235,11 @@ Session::finalize_audio_export ()
 
 	/* Clean up */
 
-	ProcessExport.clear();
-	ExportReadFinished.clear();
+	/* BOOST SIGNAL are these necessary? 
+	   ProcessExport.clear();
+	   ExportReadFinished.clear();
+	*/
+
 	export_freewheel_connection.disconnect();
 	export_handler.reset();
 	export_status.reset();
diff --git a/libs/ardour/session_handle.cc b/libs/ardour/session_handle.cc
new file mode 100644
index 0000000000..03671cfa68
--- /dev/null
+++ b/libs/ardour/session_handle.cc
@@ -0,0 +1,73 @@
+/*
+    Copyright (C) 2009 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "pbd/error.h"
+
+#include "ardour/session.h"
+#include "ardour/session_handle.h"
+
+#include "i18n.h"
+
+using namespace std;
+using namespace ARDOUR;
+using namespace PBD;
+
+SessionHandlePtr::SessionHandlePtr (Session* s)
+	: _session (s) 
+{
+	if (_session) {
+		_session_connections.add_connection (_session->GoingAway.connect (boost::bind (&SessionHandlePtr::session_going_away, this)));
+	}
+}	
+
+void
+SessionHandlePtr::set_session (Session* s)
+{
+	_session_connections.drop_connections ();
+
+	if (_session) {
+		_session = 0;
+	}
+
+	if (s) {
+		_session = s;
+		_session_connections.add_connection (_session->GoingAway.connect (boost::bind (&SessionHandlePtr::session_going_away, this)));
+	}
+}
+
+void
+SessionHandlePtr::session_going_away ()
+{
+	set_session (0);
+}
+
+/*-------------------------*/
+
+
+SessionHandleRef::SessionHandleRef (Session& s)
+	: _session (s) 
+{
+	scoped_connect (_session.GoingAway, boost::bind (&SessionHandleRef::session_going_away, this));
+}	
+
+void
+SessionHandleRef::session_going_away ()
+{
+	error << string_compose (_("programming error: %1"), "SessionHandleRef exists across sesssion deletion!") << endmsg;
+}
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index d006097f09..b2cece991c 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -208,39 +208,26 @@ Session::set_mmc_port (string port_tag)
 		mmc->set_send_device_id (old_send_device_id);
 	}
 
-	mmc->Play.connect
-		(sigc::mem_fun (*this, &Session::mmc_deferred_play));
-	mmc->DeferredPlay.connect
-		(sigc::mem_fun (*this, &Session::mmc_deferred_play));
-	mmc->Stop.connect
-		(sigc::mem_fun (*this, &Session::mmc_stop));
-	mmc->FastForward.connect
-		(sigc::mem_fun (*this, &Session::mmc_fast_forward));
-	mmc->Rewind.connect
-		(sigc::mem_fun (*this, &Session::mmc_rewind));
-	mmc->Pause.connect
-		(sigc::mem_fun (*this, &Session::mmc_pause));
-	mmc->RecordPause.connect
-		(sigc::mem_fun (*this, &Session::mmc_record_pause));
-	mmc->RecordStrobe.connect
-		(sigc::mem_fun (*this, &Session::mmc_record_strobe));
-	mmc->RecordExit.connect
-		(sigc::mem_fun (*this, &Session::mmc_record_exit));
-	mmc->Locate.connect
-		(sigc::mem_fun (*this, &Session::mmc_locate));
-	mmc->Step.connect
-		(sigc::mem_fun (*this, &Session::mmc_step));
-	mmc->Shuttle.connect
-		(sigc::mem_fun (*this, &Session::mmc_shuttle));
-	mmc->TrackRecordStatusChange.connect
-		(sigc::mem_fun (*this, &Session::mmc_record_enable));
+	scoped_connect (mmc->Play, boost::bind (&Session::mmc_deferred_play, this, _1));
+	scoped_connect (mmc->DeferredPlay, boost::bind (&Session::mmc_deferred_play, this, _1));
+	scoped_connect (mmc->Stop, boost::bind (&Session::mmc_stop, this, _1));
+	scoped_connect (mmc->FastForward, boost::bind (&Session::mmc_fast_forward, this, _1));
+	scoped_connect (mmc->Rewind, boost::bind (&Session::mmc_rewind, this, _1));
+	scoped_connect (mmc->Pause, boost::bind (&Session::mmc_pause, this, _1));
+	scoped_connect (mmc->RecordPause, boost::bind (&Session::mmc_record_pause, this, _1));
+	scoped_connect (mmc->RecordStrobe, boost::bind (&Session::mmc_record_strobe, this, _1));
+	scoped_connect (mmc->RecordExit, boost::bind (&Session::mmc_record_exit, this, _1));
+	scoped_connect (mmc->Locate, boost::bind (&Session::mmc_locate, this, _1, _2));
+	scoped_connect (mmc->Step, boost::bind (&Session::mmc_step, this, _1, _2));
+	scoped_connect (mmc->Shuttle, boost::bind (&Session::mmc_shuttle, this, _1, _2, _3));
+	scoped_connect (mmc->TrackRecordStatusChange, boost::bind (&Session::mmc_record_enable, this, _1, _2, _3));
 
 
 	/* also handle MIDI SPP because its so common */
 
-	_mmc_port->input()->start.connect (sigc::mem_fun (*this, &Session::spp_start));
-	_mmc_port->input()->contineu.connect (sigc::mem_fun (*this, &Session::spp_continue));
-	_mmc_port->input()->stop.connect (sigc::mem_fun (*this, &Session::spp_stop));
+	scoped_connect (_mmc_port->input()->start, boost::bind (&Session::spp_start, this, _1, _2));
+	scoped_connect (_mmc_port->input()->contineu, boost::bind (&Session::spp_continue, this, _1, _2));
+	scoped_connect (_mmc_port->input()->stop, boost::bind (&Session::spp_stop, this, _1, _2));
 
 	Config->set_mmc_port_name (port_tag);
 
diff --git a/libs/ardour/session_playlists.cc b/libs/ardour/session_playlists.cc
index 5af0dc4caa..ec9220ed41 100644
--- a/libs/ardour/session_playlists.cc
+++ b/libs/ardour/session_playlists.cc
@@ -16,6 +16,7 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
 */
+#include <vector>
 
 #include "pbd/xml++.h"
 #include "pbd/compose.h"
@@ -73,7 +74,7 @@ SessionPlaylists::add (boost::shared_ptr<Playlist> playlist)
 
 	if (!existing) {
 		playlists.insert (playlists.begin(), playlist);
-		playlist->InUse.connect (sigc::bind (sigc::mem_fun (*this, &SessionPlaylists::track), boost::weak_ptr<Playlist>(playlist)));
+		scoped_connect (playlist->InUse, boost::bind (&SessionPlaylists::track, this, _1, boost::weak_ptr<Playlist>(playlist)));
 	}
 
 	return existing;
@@ -265,7 +266,7 @@ SessionPlaylists::add_state (XMLNode* node, bool full_state)
 
 /** @return true for `stop cleanup', otherwise false */
 bool
-SessionPlaylists::maybe_delete_unused (sigc::signal<int, boost::shared_ptr<Playlist> > ask)
+SessionPlaylists::maybe_delete_unused (boost::function<int(boost::shared_ptr<Playlist>)> ask)
 {
 	vector<boost::shared_ptr<Playlist> > playlists_tbd;
 
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 3364de9815..4c7515f5e4 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -30,7 +30,6 @@
 #include <string>
 #include <cerrno>
 
-#include <sigc++/bind.h>
 
 #include <cstdio> /* snprintf(3) ... grrr */
 #include <cmath>
@@ -165,7 +164,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	_base_frame_rate = _current_frame_rate;
 
 	_tempo_map = new TempoMap (_current_frame_rate);
-	_tempo_map->StateChanged.connect (sigc::mem_fun (*this, &Session::tempo_map_changed));
+	scoped_connect (_tempo_map->StateChanged, boost::bind (&Session::tempo_map_changed, this, _1));
 
 
 	_non_soloed_outs_muted = false;
@@ -267,20 +266,21 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	delta_accumulator_cnt = 0;
 	_slave_state = Stopped;
 
-	_engine.GraphReordered.connect (sigc::mem_fun (*this, &Session::graph_reordered));
+	scoped_connect (_engine.GraphReordered, boost::bind (&Session::graph_reordered, this));
 
 	/* These are all static "per-class" signals */
 
-	RegionFactory::CheckNewRegion.connect (sigc::mem_fun (*this, &Session::add_region));
-	SourceFactory::SourceCreated.connect (sigc::mem_fun (*this, &Session::add_source));
-	PlaylistFactory::PlaylistCreated.connect (sigc::mem_fun (*this, &Session::add_playlist));
-	Processor::ProcessorCreated.connect (sigc::mem_fun (*this, &Session::add_processor));
-	NamedSelection::NamedSelectionCreated.connect (sigc::mem_fun (*this, &Session::add_named_selection));
-	AutomationList::AutomationListCreated.connect (sigc::mem_fun (*this, &Session::add_automation_list));
+	scoped_connect (RegionFactory::CheckNewRegion, boost::bind (&Session::add_region, this, _1));
+	scoped_connect (SourceFactory::SourceCreated, boost::bind (&Session::add_source, this, _1));
+	scoped_connect (PlaylistFactory::PlaylistCreated, boost::bind (&Session::add_playlist, this, _1, _2));
+	scoped_connect (Processor::ProcessorCreated, boost::bind (&Session::add_processor, this, _1));
+	scoped_connect (NamedSelection::NamedSelectionCreated, boost::bind (&Session::add_named_selection, this, _1));
+	scoped_connect (AutomationList::AutomationListCreated, boost::bind (&Session::add_automation_list, this, _1));
 
-	Controllable::Destroyed.connect (sigc::mem_fun (*this, &Session::remove_controllable));
+	// BOOST SIGNALS
+	// scoped_connect (Controllable::Destroyed, boost::bind (&Session::remove_controllable, this, _1));
 
-	IO::PortCountChanged.connect (sigc::mem_fun (*this, &Session::ensure_buffers));
+	scoped_connect (IO::PortCountChanged, boost::bind (&Session::ensure_buffers, this, _1));
 
 	/* stop IO objects from doing stuff until we're ready for them */
 
@@ -332,15 +332,15 @@ Session::second_stage_init (bool new_session)
 	_state_of_the_state = StateOfTheState (_state_of_the_state|CannotSave|Loading);
 
 
-	_locations.changed.connect (sigc::mem_fun (this, &Session::locations_changed));
-	_locations.added.connect (sigc::mem_fun (this, &Session::locations_added));
+	scoped_connect (_locations.changed, boost::bind (&Session::locations_changed, this));
+	scoped_connect (_locations.added, boost::bind (&Session::locations_added, this, _1));
 	setup_click_sounds (0);
 	setup_midi_control ();
 
 	/* Pay attention ... */
 
-	_engine.Halted.connect (sigc::mem_fun (*this, &Session::engine_halted));
-	_engine.Xrun.connect (sigc::mem_fun (*this, &Session::xrun_recovery));
+	scoped_connect (_engine.Halted, boost::bind (&Session::engine_halted, this));
+	scoped_connect (_engine.Xrun, boost::bind (&Session::xrun_recovery, this));
 
 	try {
 		when_engine_running();
@@ -364,14 +364,14 @@ Session::second_stage_init (bool new_session)
 	deliver_mmc (MIDI::MachineControl::cmdMmcReset, 0);
 	deliver_mmc (MIDI::MachineControl::cmdLocate, 0);
 
-	MidiClockTicker::instance().set_session(*this);
-	MIDI::Name::MidiPatchManager::instance().set_session(*this);
+	MidiClockTicker::instance().set_session (this);
+	MIDI::Name::MidiPatchManager::instance().set_session (this);
 
 	/* initial program change will be delivered later; see ::config_changed() */
 
 	BootMessage (_("Reset Control Protocols"));
 
-	ControlProtocolManager::instance().set_session (*this);
+	ControlProtocolManager::instance().set_session (this);
 
 	config.set_end_marker_is_free (new_session);
 
@@ -2311,11 +2311,12 @@ Session::cleanup_sources (CleanupReport& rep)
 
 	/* step 1: consider deleting all unused playlists */
 	
-	if (playlists->maybe_delete_unused (AskAboutPlaylistDeletion)) {
+/* BOOST SIGNALS
+	if (playlists->maybe_delete_unused (boost::bind (AskAboutPlaylistDeletion, _1));
 		ret = 0;
 		goto out;
 	}
-
+*/
 	/* step 2: find all un-used sources */
 
 	rep.paths.clear ();
@@ -2334,7 +2335,7 @@ Session::cleanup_sources (CleanupReport& rep)
 
 		if (!playlists->source_use_count(i->second) && i->second->length(i->second->timeline_position()) > 0) {
 			dead_sources.push_back (i->second);
-			i->second->GoingAway();
+			i->second->drop_references ();
 		}
 
 		i = tmp;
@@ -2653,8 +2654,7 @@ Session::remove_controllable (Controllable* c)
 
 	Glib::Mutex::Lock lm (controllables_lock);
 
-	Controllables::iterator x = controllables.find(
-		 boost::shared_ptr<Controllable>(c, null_deleter()));
+	Controllables::iterator x = controllables.find (boost::shared_ptr<Controllable>(c, null_deleter()));
 
 	if (x != controllables.end()) {
 		controllables.erase (x);
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index 63bb4c4213..0e808accb7 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -21,8 +21,6 @@
 #include <cerrno>
 #include <unistd.h>
 
-#include <sigc++/bind.h>
-#include <sigc++/retype.h>
 
 #include "pbd/undo.h"
 #include "pbd/error.h"
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index 7f66486425..64cad0f2b6 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -193,7 +193,7 @@ SndFileSource::init_sndfile ()
 	}
 
 	AudioFileSource::HeaderPositionOffsetChanged.connect (
-			sigc::mem_fun (*this, &SndFileSource::handle_header_position_change));
+			boost::bind (&SndFileSource::handle_header_position_change, this));
 }
 
 int
@@ -247,7 +247,7 @@ SndFileSource::open ()
 
 SndFileSource::~SndFileSource ()
 {
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 
 	if (sf) {
 		sf_close (sf);
diff --git a/libs/ardour/source.cc b/libs/ardour/source.cc
index 958bc2c1b5..a8c4262a66 100644
--- a/libs/ardour/source.cc
+++ b/libs/ardour/source.cc
@@ -76,7 +76,6 @@ Source::Source (Session& s, const XMLNode& node)
 Source::~Source ()
 {
 	DEBUG_TRACE (DEBUG::Destruction, string_compose ("Source %1 destructor\n", _name));
-	notify_callbacks ();
 }
 
 
diff --git a/libs/ardour/source_factory.cc b/libs/ardour/source_factory.cc
index a44a372726..e401b010ea 100644
--- a/libs/ardour/source_factory.cc
+++ b/libs/ardour/source_factory.cc
@@ -50,7 +50,7 @@ using namespace ARDOUR;
 using namespace std;
 using namespace PBD;
 
-sigc::signal<void,boost::shared_ptr<Source> > SourceFactory::SourceCreated;
+boost::signals2::signal<void(boost::shared_ptr<Source>)> SourceFactory::SourceCreated;
 Glib::Cond* SourceFactory::PeaksToBuild;
 Glib::StaticMutex SourceFactory::peak_building_lock = GLIBMM_STATIC_MUTEX_INIT;
 std::list<boost::weak_ptr<AudioSource> > SourceFactory::files_with_peaks;
diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 2dc5eeaada..9536576713 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -24,7 +24,6 @@
 
 #include <cmath>
 
-#include <sigc++/bind.h>
 
 #include <glibmm/thread.h>
 #include "pbd/xml++.h"
diff --git a/libs/ardour/ticker.cc b/libs/ardour/ticker.cc
index ab0a7144a8..0a6bb8b20b 100644
--- a/libs/ardour/ticker.cc
+++ b/libs/ardour/ticker.cc
@@ -27,37 +27,37 @@
 using namespace std;
 #endif
 
-namespace ARDOUR
-{
-
+using namespace ARDOUR;
 
-void Ticker::set_session(Session& s)
+void Ticker::set_session (Session* s)
 {
-	 _session = &s;
+	SessionHandlePtr::set_session (s);
 
-	 if (_session) {
-		 _session->tick.connect(sigc::mem_fun (*this, &Ticker::tick));
-		 _session->GoingAway.connect(sigc::mem_fun (*this, &Ticker::going_away));
-	 }
+	if (_session) {
+		_session_connections.add_connection (_session->tick.connect (boost::bind (&Ticker::tick, this, _1, _2, _3)));
+	}
 }
 
-void MidiClockTicker::set_session(Session& s)
+void MidiClockTicker::set_session (Session* s)
 {
-	 Ticker::set_session(s);
+	 Ticker::set_session (s);
 
 	 if (_session) {
-		 _session->MIDIClock_PortChanged.connect(
-				 sigc::mem_fun (*this, &MidiClockTicker::update_midi_clock_port));
-		 _session->TransportStateChange.connect(
-				 sigc::mem_fun (*this, &MidiClockTicker::transport_state_changed));
-		 _session->PositionChanged.connect(
-				 sigc::mem_fun (*this, &MidiClockTicker::position_changed));
-		 _session->TransportLooped.connect(
-				 sigc::mem_fun (*this, &MidiClockTicker::transport_looped));
+		 _session_connections.add_connection (_session->MIDIClock_PortChanged.connect (boost::bind (&MidiClockTicker::update_midi_clock_port, this)));
+		 _session_connections.add_connection (_session->TransportStateChange.connect (boost::bind (&MidiClockTicker::transport_state_changed, this)));
+		 _session_connections.add_connection (_session->PositionChanged.connect (boost::bind (&MidiClockTicker::position_changed, this, _1)));
+		 _session_connections.add_connection (_session->TransportLooped.connect (boost::bind (&MidiClockTicker::transport_looped, this)));
 		 update_midi_clock_port();
 	 }
 }
 
+void
+MidiClockTicker::session_going_away ()
+{
+	SessionHandlePtr::session_going_away(); 
+	_midi_port = 0; 
+}
+
 void MidiClockTicker::update_midi_clock_port()
 {
 	 _midi_port = _session->midi_clock_port();
@@ -225,5 +225,5 @@ void MidiClockTicker::send_stop_event(nframes_t offset)
 	_midi_port->write(_midi_clock_tick, 1, offset);
 }
 
-}
+
 
diff --git a/libs/ardour/track.cc b/libs/ardour/track.cc
index acfc9258b4..7d19d23007 100644
--- a/libs/ardour/track.cc
+++ b/libs/ardour/track.cc
@@ -16,9 +16,6 @@
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 #include "pbd/error.h"
-#include <sigc++/retype.h>
-#include <sigc++/retype_return.h>
-#include <sigc++/bind.h>
 
 #include "ardour/amp.h"
 #include "ardour/audioplaylist.h"
diff --git a/libs/ardour/vst_plugin.cc b/libs/ardour/vst_plugin.cc
index 81e9674f1a..ee3ebd2ee3 100644
--- a/libs/ardour/vst_plugin.cc
+++ b/libs/ardour/vst_plugin.cc
@@ -102,7 +102,7 @@ VSTPlugin::VSTPlugin (const VSTPlugin &other)
 VSTPlugin::~VSTPlugin ()
 {
 	deactivate ();
-	GoingAway (); /* EMIT SIGNAL */
+	drop_references ();
 	fst_close (_fst);
 }
 
diff --git a/libs/ardour/wscript b/libs/ardour/wscript
index 0dcfea7056..97ad05cb68 100644
--- a/libs/ardour/wscript
+++ b/libs/ardour/wscript
@@ -164,6 +164,7 @@ libardour_sources = [
 	'session_directory.cc',
 	'session_events.cc',
 	'session_export.cc',
+	'session_handle.cc',
 	'session_metadata.cc',
 	'session_midi.cc',
 	'session_playlists.cc',
diff --git a/libs/gtkmm2ext/binding_proxy.cc b/libs/gtkmm2ext/binding_proxy.cc
index d0696b105f..140dea7e5b 100644
--- a/libs/gtkmm2ext/binding_proxy.cc
+++ b/libs/gtkmm2ext/binding_proxy.cc
@@ -88,7 +88,7 @@ BindingProxy::button_press_handler (GdkEventButton *ev)
 			}
 			prompter->set_text (prompt);
 			prompter->touch (); // shows popup
-			learning_connection = controllable->LearningFinished.connect (mem_fun (*this, &BindingProxy::learning_finished));
+			learning_connection = controllable->LearningFinished.connect (boost::bind (&BindingProxy::learning_finished, this));
 		}
 		return true;
 	}
diff --git a/libs/gtkmm2ext/gtkmm2ext/binding_proxy.h b/libs/gtkmm2ext/gtkmm2ext/binding_proxy.h
index f684cce5c3..348f9f2649 100644
--- a/libs/gtkmm2ext/gtkmm2ext/binding_proxy.h
+++ b/libs/gtkmm2ext/gtkmm2ext/binding_proxy.h
@@ -22,9 +22,9 @@
 #define __binding_proxy__
 
 #include <string>
-
 #include <gtkmm2ext/popup.h>
 #include <boost/shared_ptr.hpp>
+#include <boost/signals2.hpp>
 
 namespace PBD {
 	class Controllable;
@@ -50,7 +50,7 @@ class BindingProxy : public sigc::trackable
 	boost::shared_ptr<PBD::Controllable> controllable;
 	guint bind_button;
 	guint bind_statemask;
-	sigc::connection learning_connection;
+	boost::signals2::scoped_connection learning_connection;
 	void learning_finished ();
 	bool prompter_hiding (GdkEventAny *);
 };
diff --git a/libs/gtkmm2ext/gtkmm2ext/gtk_ui.h b/libs/gtkmm2ext/gtkmm2ext/gtk_ui.h
index bac657a028..1fbfb9d800 100644
--- a/libs/gtkmm2ext/gtkmm2ext/gtk_ui.h
+++ b/libs/gtkmm2ext/gtkmm2ext/gtk_ui.h
@@ -123,6 +123,10 @@ class UI : public Receiver, public AbstractUI<UIRequest>
 		Glib::signal_idle().connect (bind (slot (&UI::idle_delete<T>), obj));
 	}
 
+	template<class T> void delete_in_self (T *obj) {
+		call_slot (boost::bind (&UI::delete_in_self, this, obj));
+	}
+
 	Gdk::Color get_color (const std::string& prompt, bool& picked, const Gdk::Color *initial = 0);
 
 	/* starting is sent just before we enter the main loop,
diff --git a/libs/midi++2/channel.cc b/libs/midi++2/channel.cc
index f19c913644..9e339654b4 100644
--- a/libs/midi++2/channel.cc
+++ b/libs/midi++2/channel.cc
@@ -23,7 +23,6 @@
 #include "midi++/port.h"
 #include "midi++/channel.h"
 
-using namespace sigc;
 using namespace MIDI;
 
 Channel::Channel (byte channelnum, Port &p) : _port (p)
@@ -35,44 +34,45 @@ Channel::Channel (byte channelnum, Port &p) : _port (p)
 
 void
 Channel::connect_input_signals ()
-
 {
-	_port.input()->channel_pressure[_channel_number].connect
-		(mem_fun (*this, &Channel::process_chanpress));
-	_port.input()->channel_note_on[_channel_number].connect
-		(mem_fun (*this, &Channel::process_note_on));
-	_port.input()->channel_note_off[_channel_number].connect
-		(mem_fun (*this, &Channel::process_note_off));
-	_port.input()->channel_poly_pressure[_channel_number].connect
-		(mem_fun (*this, &Channel::process_polypress));
-	_port.input()->channel_program_change[_channel_number].connect
-		(mem_fun (*this, &Channel::process_program_change));
-	_port.input()->channel_controller[_channel_number].connect
-		(mem_fun (*this, &Channel::process_controller));
-	_port.input()->channel_pitchbend[_channel_number].connect
-		(mem_fun (*this, &Channel::process_pitchbend));
-	_port.input()->reset.connect (mem_fun (*this, &Channel::process_reset));
+	add_connection (_port.input()->channel_pressure[_channel_number].connect
+			(boost::bind (&Channel::process_chanpress, this, _1, _2)));
+	add_connection (_port.input()->channel_note_on[_channel_number].connect
+			(boost::bind (&Channel::process_note_on, this, _1, _2)));
+	add_connection (_port.input()->channel_note_off[_channel_number].connect
+			(boost::bind (&Channel::process_note_off, this, _1, _2)));
+	add_connection (_port.input()->channel_poly_pressure[_channel_number].connect
+			(boost::bind (&Channel::process_polypress, this, _1, _2)));
+	add_connection (_port.input()->channel_program_change[_channel_number].connect
+			(boost::bind (&Channel::process_program_change, this, _1, _2)));
+	add_connection (_port.input()->channel_controller[_channel_number].connect
+			(boost::bind (&Channel::process_controller, this, _1, _2)));
+	add_connection (_port.input()->channel_pitchbend[_channel_number].connect
+			(boost::bind (&Channel::process_pitchbend, this, _1, _2)));
+
+	add_connection (_port.input()->reset.connect (boost::bind (&Channel::process_reset, this, _1)));
 }
 
 void
 Channel::connect_output_signals ()
 
 {
-	_port.output()->channel_pressure[_channel_number].connect
-		(mem_fun (*this, &Channel::process_chanpress));
-	_port.output()->channel_note_on[_channel_number].connect
-		(mem_fun (*this, &Channel::process_note_on));
-	_port.output()->channel_note_off[_channel_number].connect
-		(mem_fun (*this, &Channel::process_note_off));
-	_port.output()->channel_poly_pressure[_channel_number].connect
-		(mem_fun (*this, &Channel::process_polypress));
-	_port.output()->channel_program_change[_channel_number].connect
-		(mem_fun (*this, &Channel::process_program_change));
-	_port.output()->channel_controller[_channel_number].connect
-		(mem_fun (*this, &Channel::process_controller));
-	_port.output()->channel_pitchbend[_channel_number].connect
-		(mem_fun (*this, &Channel::process_pitchbend));
-	_port.output()->reset.connect (mem_fun (*this, &Channel::process_reset));
+	add_connection (_port.output()->channel_pressure[_channel_number].connect
+			(boost::bind (&Channel::process_chanpress, this, _1, _2)));
+	add_connection (_port.output()->channel_note_on[_channel_number].connect
+			(boost::bind (&Channel::process_note_on, this, _1, _2)));
+	add_connection (_port.output()->channel_note_off[_channel_number].connect
+			(boost::bind (&Channel::process_note_off, this, _1, _2)));
+	add_connection (_port.output()->channel_poly_pressure[_channel_number].connect
+			(boost::bind (&Channel::process_polypress, this, _1, _2)));
+	add_connection (_port.output()->channel_program_change[_channel_number].connect
+			(boost::bind (&Channel::process_program_change, this, _1, _2)));
+	add_connection (_port.output()->channel_controller[_channel_number].connect
+			(boost::bind (&Channel::process_controller, this, _1, _2)));
+	add_connection (_port.output()->channel_pitchbend[_channel_number].connect
+			(boost::bind (&Channel::process_pitchbend, this, _1, _2)));
+
+	add_connection (_port.output()->reset.connect (boost::bind (&Channel::process_reset, this, _1)));
 }
 
 void
diff --git a/libs/midi++2/midi++/channel.h b/libs/midi++2/midi++/channel.h
index 697f2a1e46..617ae14430 100644
--- a/libs/midi++2/midi++/channel.h
+++ b/libs/midi++2/midi++/channel.h
@@ -22,7 +22,8 @@
 
 #include <queue>
 
-#include <sigc++/sigc++.h>
+#include <boost/signals2.hpp>
+#include "pbd/scoped_connections.h"
 
 #include "midi++/types.h"
 #include "midi++/parser.h"
@@ -36,7 +37,7 @@ class Port;
  * This remembers various useful information about the current 'state' of a
  * MIDI channel (eg current pitch bend value).
  */
-class Channel : public sigc::trackable {
+class Channel : public PBD::ScopedConnectionList {
 
   public:
 	Channel (byte channel_number, Port &);
diff --git a/libs/midi++2/midi++/manager.h b/libs/midi++2/midi++/manager.h
index 8c665d0086..d451d234c8 100644
--- a/libs/midi++2/midi++/manager.h
+++ b/libs/midi++2/midi++/manager.h
@@ -83,7 +83,7 @@ class Manager {
 
 	int get_known_ports (std::vector<PortSet>&);
 
-	sigc::signal<void> PortsChanged;
+	boost::signals2::signal<void()> PortsChanged;
 
   private:
 	/* This is a SINGLETON pattern */
diff --git a/libs/midi++2/midi++/mmc.h b/libs/midi++2/midi++/mmc.h
index 4506bd8a4b..0b06222438 100644
--- a/libs/midi++2/midi++/mmc.h
+++ b/libs/midi++2/midi++/mmc.h
@@ -20,7 +20,8 @@
 #ifndef __midipp_mmc_h_h__
 #define __midipp_mmc_h_h__
 
-#include <sigc++/sigc++.h>
+#include <boost/signals2.hpp>
+
 #include "midi++/types.h"
 
 namespace MIDI {
@@ -28,10 +29,10 @@ namespace MIDI {
 class Port;
 class Parser;
 
-class MachineControl : public sigc::trackable
-
+class MachineControl 
 {
   public:
+	typedef boost::signals2::signal<void(MachineControl&)> MMCSignal;
 	typedef byte CommandSignature[60];
 	typedef byte ResponseSignature[60];
 
@@ -102,63 +103,61 @@ class MachineControl : public sigc::trackable
 	   when certain MMC commands are received.
 	*/
 			
-	sigc::signal<void,MachineControl &> Stop;
-	sigc::signal<void,MachineControl &> Play;
-	sigc::signal<void,MachineControl &> DeferredPlay;
-	sigc::signal<void,MachineControl &> FastForward;
-	sigc::signal<void,MachineControl &> Rewind;
-	sigc::signal<void,MachineControl &> RecordStrobe;
-	sigc::signal<void,MachineControl &> RecordExit;
-	sigc::signal<void,MachineControl &> RecordPause;
-	sigc::signal<void,MachineControl &> Pause;
-	sigc::signal<void,MachineControl &> Eject;
-	sigc::signal<void,MachineControl &> Chase;
-	sigc::signal<void,MachineControl &> CommandErrorReset;
-	sigc::signal<void,MachineControl &> MmcReset;
-
-	sigc::signal<void,MachineControl &> JogStart;
-	sigc::signal<void,MachineControl &> JogStop;
-
-	sigc::signal<void,MachineControl &> Write;
-	sigc::signal<void,MachineControl &> MaskedWrite;
-	sigc::signal<void,MachineControl &> Read;
-	sigc::signal<void,MachineControl &> Update;
-	sigc::signal<void,MachineControl &> VariablePlay;
-	sigc::signal<void,MachineControl &> Search;
-	sigc::signal<void,MachineControl &> AssignSystemMaster;
-	sigc::signal<void,MachineControl &> GeneratorCommand;
-	sigc::signal<void,MachineControl &> MidiTimeCodeCommand;
-	sigc::signal<void,MachineControl &> Move;
-	sigc::signal<void,MachineControl &> Add;
-	sigc::signal<void,MachineControl &> Subtract;
-	sigc::signal<void,MachineControl &> DropFrameAdjust;
-	sigc::signal<void,MachineControl &> Procedure;
-	sigc::signal<void,MachineControl &> Event;
-	sigc::signal<void,MachineControl &> Group;
-	sigc::signal<void,MachineControl &> CommandSegment;
-	sigc::signal<void,MachineControl &> DeferredVariablePlay;
-	sigc::signal<void,MachineControl &> RecordStrobeVariable;
-	sigc::signal<void,MachineControl &> Wait;
-	sigc::signal<void,MachineControl &> Resume;
+	MMCSignal Stop;
+	MMCSignal Play;
+	MMCSignal DeferredPlay;
+	MMCSignal FastForward;
+	MMCSignal Rewind;
+	MMCSignal RecordStrobe;
+	MMCSignal RecordExit;
+	MMCSignal RecordPause;
+	MMCSignal Pause;
+	MMCSignal Eject;
+	MMCSignal Chase;
+	MMCSignal CommandErrorReset;
+	MMCSignal MmcReset;
+	MMCSignal JogStart;
+	MMCSignal JogStop;
+	MMCSignal Write;
+	MMCSignal MaskedWrite;
+	MMCSignal Read;
+	MMCSignal Update;
+	MMCSignal VariablePlay;
+	MMCSignal Search;
+	MMCSignal AssignSystemMaster;
+	MMCSignal GeneratorCommand;
+	MMCSignal MidiTimeCodeCommand;
+	MMCSignal Move;
+	MMCSignal Add;
+	MMCSignal Subtract;
+	MMCSignal DropFrameAdjust;
+	MMCSignal Procedure;
+	MMCSignal Event;
+	MMCSignal Group;
+	MMCSignal CommandSegment;
+	MMCSignal DeferredVariablePlay;
+	MMCSignal RecordStrobeVariable;
+	MMCSignal Wait;
+	MMCSignal Resume;
 
 	/* The second argument is the shuttle speed, the third is
 	   true if the direction is "forwards", false for "reverse"
 	*/
 	
-	sigc::signal<void,MachineControl &,float,bool> Shuttle;
+	boost::signals2::signal<void(MachineControl&,float,bool)> Shuttle;
 
 	/* The second argument specifies the desired track record enabled
 	   status.
 	*/
 
-	sigc::signal<void,MachineControl &,size_t,bool> 
+	boost::signals2::signal<void(MachineControl &,size_t,bool)> 
 		                             TrackRecordStatusChange;
 	
 	/* The second argument specifies the desired track record enabled
 	   status.
 	*/
 
-	sigc::signal<void,MachineControl &,size_t,bool> 
+	boost::signals2::signal<void(MachineControl &,size_t,bool)> 
 		                             TrackMuteChange;
 	
 	/* The second argument points to a byte array containing
@@ -166,11 +165,11 @@ class MachineControl : public sigc::trackable
 	   format (5 bytes, roughly: hrs/mins/secs/frames/subframes)
 	*/
 
-	sigc::signal<void,MachineControl &, const byte *> Locate;
+	boost::signals2::signal<void(MachineControl &, const byte *)> Locate;
 
 	/* The second argument is the number of steps to jump */
 	
-	sigc::signal<void,MachineControl &, int> Step;
+	boost::signals2::signal<void(MachineControl &, int)> Step;
 	
   protected:
 
@@ -258,7 +257,8 @@ class MachineControl : public sigc::trackable
 	MIDI::Port &_port;
 
 	void process_mmc_message (Parser &p, byte *, size_t len);
-	
+	boost::signals2::scoped_connection mmc_connection;
+
 	int  do_masked_write (byte *, size_t len);
 	int  do_locate (byte *, size_t len);
 	int  do_step (byte *, size_t len);
diff --git a/libs/midi++2/midi++/parser.h b/libs/midi++2/midi++/parser.h
index 365f2fb46a..497a50abe8 100644
--- a/libs/midi++2/midi++/parser.h
+++ b/libs/midi++2/midi++/parser.h
@@ -23,7 +23,7 @@
 #include <string>
 #include <iostream>
 
-#include <sigc++/sigc++.h>
+#include <boost/signals2.hpp>
 
 #include "midi++/types.h"
 
@@ -32,12 +32,14 @@ namespace MIDI {
 class Port;
 class Parser;
 
-typedef sigc::signal<void, Parser &, byte>                 OneByteSignal;
-typedef sigc::signal<void, Parser &, EventTwoBytes *>      TwoByteSignal;
-typedef sigc::signal<void, Parser &, pitchbend_t>          PitchBendSignal;
-typedef sigc::signal<void, Parser &, byte *, size_t> Signal;
+typedef boost::signals2::signal<void(Parser&)>                   ZeroByteSignal;
+typedef boost::signals2::signal<void(Parser&,nframes_t)>         TimestampedSignal;
+typedef boost::signals2::signal<void(Parser&, byte)>             OneByteSignal;
+typedef boost::signals2::signal<void(Parser &, EventTwoBytes *)> TwoByteSignal;
+typedef boost::signals2::signal<void(Parser &, pitchbend_t)>     PitchBendSignal;
+typedef boost::signals2::signal<void(Parser &, byte *, size_t)>  Signal;
 
-class Parser : public sigc::trackable {
+class Parser {
  public:
 	Parser (Port &p);
 	~Parser ();
@@ -69,8 +71,8 @@ class Parser : public sigc::trackable {
 	OneByteSignal         channel_program_change[16];
 	PitchBendSignal       channel_pitchbend[16];
 	TwoByteSignal         channel_controller[16];
-	sigc::signal<void, Parser &>          channel_active_preparse[16];
-	sigc::signal<void, Parser &>          channel_active_postparse[16];
+	ZeroByteSignal        channel_active_preparse[16];
+	ZeroByteSignal        channel_active_postparse[16];
 
 	OneByteSignal         mtc_quarter_frame; /* see below for more useful signals */
 	Signal                mtc;
@@ -82,15 +84,16 @@ class Parser : public sigc::trackable {
 	Signal                position;
 	Signal                song;
 
-	sigc::signal<void, Parser &>                     all_notes_off;
-	sigc::signal<void, Parser &>                     tune;
-	sigc::signal<void, Parser &, nframes_t>          timing;
-	sigc::signal<void, Parser &, nframes_t>          start;
-	sigc::signal<void, Parser &, nframes_t>          stop;
-	sigc::signal<void, Parser &, nframes_t>          contineu;  /* note spelling */
-	sigc::signal<void, Parser &>          active_sense;
-	sigc::signal<void, Parser &>          reset;
-	sigc::signal<void, Parser &>          eox;
+	ZeroByteSignal        all_notes_off;
+	ZeroByteSignal        tune;
+	ZeroByteSignal        active_sense;
+	ZeroByteSignal        reset;
+	ZeroByteSignal        eox;
+
+	TimestampedSignal     timing;
+	TimestampedSignal     start;
+	TimestampedSignal     stop;
+	TimestampedSignal     contineu;  /* note spelling */
 
 	/* This should really be protected, but then derivatives of Port
 	   can't access it.
@@ -106,9 +109,9 @@ class Parser : public sigc::trackable {
 
 	void set_offline (bool);
 	bool offline() const { return _offline; }
-	sigc::signal<void> OfflineStatusChanged;
+	boost::signals2::signal<void()> OfflineStatusChanged;
 
-	sigc::signal<int, byte *, size_t> edit;
+	boost::signals2::signal<int(byte *, size_t)> edit;
 
 	void set_mmc_forwarding (bool yn) {
 		_mmc_forward = yn;
@@ -121,10 +124,10 @@ class Parser : public sigc::trackable {
 	const byte *mtc_current() const { return _mtc_time; }
 	bool        mtc_locked() const  { return _mtc_locked; }
 	
-	sigc::signal<void,Parser&,int,nframes_t>      mtc_qtr;
-	sigc::signal<void,const byte*,bool,nframes_t> mtc_time;
-	sigc::signal<void,MTC_Status>                 mtc_status;
-	sigc::signal<bool>                            mtc_skipped;
+	boost::signals2::signal<void(Parser&,int,nframes_t)>      mtc_qtr;
+	boost::signals2::signal<void(const byte*,bool,nframes_t)> mtc_time;
+	boost::signals2::signal<void(MTC_Status)>                 mtc_status;
+	boost::signals2::signal<bool()>                           mtc_skipped;
 
 	void set_mtc_forwarding (bool yn) {
 		_mtc_forward = yn;
@@ -139,7 +142,7 @@ class Parser : public sigc::trackable {
 	std::ostream *trace_stream;
 	std::string trace_prefix;
 	void trace_event (Parser &p, byte *msg, size_t len);
-	sigc::connection trace_connection;
+	boost::signals2::scoped_connection trace_connection;
 
 	size_t message_counter[256];
 
diff --git a/libs/midi++2/midi++/port.h b/libs/midi++2/midi++/port.h
index 23a9a01200..0c5fe4ae37 100644
--- a/libs/midi++2/midi++/port.h
+++ b/libs/midi++2/midi++/port.h
@@ -22,7 +22,7 @@
 #include <string>
 #include <iostream>
 
-#include <sigc++/sigc++.h>
+#include <boost/signals2.hpp>
 #include "pbd/xml++.h"
 
 #include "midi++/types.h"
@@ -33,7 +33,7 @@ namespace MIDI {
 class Channel;
 class PortRequest;
 
-class Port : public sigc::trackable {
+class Port {
   public:
 	enum Type {
 		Unknown,
@@ -168,7 +168,6 @@ class Port : public sigc::trackable {
 	int              _mode;
 	size_t           _number;
 	Channel          *_channel[16];
-	sigc::connection thru_connection;
 	unsigned int     bytes_written;
 	unsigned int     bytes_read;
 	Parser           *input_parser;
diff --git a/libs/midi++2/mmc.cc b/libs/midi++2/mmc.cc
index 2e42bb59fc..e496e37aa9 100644
--- a/libs/midi++2/mmc.cc
+++ b/libs/midi++2/mmc.cc
@@ -206,8 +206,7 @@ MachineControl::MachineControl (Port &p, float /*version*/,
 	_send_device_id = 0x7f;
 	
 	if ((parser = _port.input()) != 0) {
-		parser->mmc.connect 
-			(mem_fun (*this, &MachineControl::process_mmc_message));
+		mmc_connection = parser->mmc.connect (boost::bind (&MachineControl::process_mmc_message, this, _1, _2, _3));
 	} else {
 		warning << "MMC connected to a non-input port: useless!"
 			<< endmsg;
diff --git a/libs/midi++2/parser.cc b/libs/midi++2/parser.cc
index 6daed45d23..4f19c40ebe 100644
--- a/libs/midi++2/parser.cc
+++ b/libs/midi++2/parser.cc
@@ -35,7 +35,6 @@
 #include "pbd/transmitter.h"
 
 using namespace std;
-using namespace sigc;
 using namespace MIDI;
 
 const char *
@@ -317,7 +316,7 @@ Parser::trace (bool onoff, ostream *o, const string &prefix)
 		cerr << "enabling tracing for port " << _port.name() << endl;
 		trace_stream = o;
 		trace_prefix = prefix;
-		trace_connection = any.connect (mem_fun (*this, &Parser::trace_event));
+		trace_connection = any.connect (boost::bind (&Parser::trace_event, this, _1, _2, _3));
 	} else {
 		trace_prefix = "";
 		trace_stream = 0;
diff --git a/libs/pbd/controllable.cc b/libs/pbd/controllable.cc
index 35f7605541..369e2bd545 100644
--- a/libs/pbd/controllable.cc
+++ b/libs/pbd/controllable.cc
@@ -26,11 +26,11 @@
 using namespace PBD;
 using namespace std;
 
-sigc::signal<void,Controllable*> Controllable::Destroyed;
-sigc::signal<bool,Controllable*> Controllable::StartLearning;
-sigc::signal<void,Controllable*> Controllable::StopLearning;
-sigc::signal<void,Controllable*,int,int> Controllable::CreateBinding;
-sigc::signal<void,Controllable*> Controllable::DeleteBinding;
+boost::signals2::signal<void(Controllable*)> Controllable::Destroyed;
+boost::signals2::signal<bool(Controllable*)> Controllable::StartLearning;
+boost::signals2::signal<void(Controllable*)> Controllable::StopLearning;
+boost::signals2::signal<void(Controllable*,int,int)> Controllable::CreateBinding;
+boost::signals2::signal<void(Controllable*)> Controllable::DeleteBinding;
 
 Glib::StaticRWLock Controllable::registry_lock = GLIBMM_STATIC_RW_LOCK_INIT;
 Controllable::Controllables Controllable::registry;
@@ -41,45 +41,47 @@ Controllable::Controllable (const string& name, const string& uri)
 	, _uri (uri)
 	, _touching (false)
 {
-	add ();
+	add (*this);
 }
 
 void
-Controllable::add ()
+Controllable::add (Controllable& ctl)
 {
+	using namespace boost;
+
 	Glib::RWLock::WriterLock lm (registry_lock);
-	registry.insert (this);
+	registry.insert (&ctl);
 
-	if (!_uri.empty()) {
+	if (!ctl.uri().empty()) {
 		pair<string,Controllable*> newpair;
-		newpair.first = _uri;
-		newpair.second = this;
+		newpair.first = ctl.uri();
+		newpair.second = &ctl;
 		registry_by_uri.insert (newpair);
 	}
 
-	this->GoingAway.connect (mem_fun (this, &Controllable::remove));
+	/* Controllable::remove() is static - no need to manage this connection */
+
+	ctl.GoingAway.connect (boost::bind (&Controllable::remove, ref (ctl)));
 }
 
 void
-Controllable::remove ()
+Controllable::remove (Controllable& ctl)
 {
 	Glib::RWLock::WriterLock lm (registry_lock);
 
 	for (Controllables::iterator i = registry.begin(); i != registry.end(); ++i) {
-		if ((*i) == this) {
+		if ((*i) == &ctl) {
 			registry.erase (i);
 			break;
 		}
 	}
 
-	if (!_uri.empty()) {
-		ControllablesByURI::iterator i = registry_by_uri.find (_uri);
+	if (!ctl.uri().empty()) {
+		ControllablesByURI::iterator i = registry_by_uri.find (ctl.uri());
 		if (i != registry_by_uri.end()) {
 			registry_by_uri.erase (i);
 		}
 	}
-
-
 }
 
 void
diff --git a/libs/pbd/pbd/command.h b/libs/pbd/pbd/command.h
index 7af7f7bb98..5a7290bc89 100644
--- a/libs/pbd/pbd/command.h
+++ b/libs/pbd/pbd/command.h
@@ -1,3 +1,4 @@
+
 /* 
     Copyright (C) 2006 Paul Davis
     Author: Hans Fugal
diff --git a/libs/pbd/pbd/controllable.h b/libs/pbd/pbd/controllable.h
index 9750ebe56e..dbec03b396 100644
--- a/libs/pbd/pbd/controllable.h
+++ b/libs/pbd/pbd/controllable.h
@@ -24,8 +24,7 @@ v    it under the terms of the GNU General Public License as published by
 #include <set>
 #include <map>
 
-#include <sigc++/trackable.h>
-#include <sigc++/signal.h>
+#include <boost/signals2.hpp>
 #include <glibmm/thread.h>
 
 #include "pbd/statefuldestructible.h"
@@ -45,16 +44,16 @@ class Controllable : public PBD::StatefulDestructible {
 	virtual void set_value (float) = 0;
 	virtual float get_value (void) const = 0;
 
-	sigc::signal<void> LearningFinished;
-	static sigc::signal<void,PBD::Controllable*,int,int> CreateBinding;
-	static sigc::signal<void,PBD::Controllable*> DeleteBinding;
+	boost::signals2::signal<void()> LearningFinished;
+	static boost::signals2::signal<void(PBD::Controllable*,int,int)> CreateBinding;
+	static boost::signals2::signal<void(PBD::Controllable*)> DeleteBinding;
 
-	static sigc::signal<bool,PBD::Controllable*> StartLearning;
-	static sigc::signal<void,PBD::Controllable*> StopLearning;
+	static boost::signals2::signal<bool(PBD::Controllable*)> StartLearning;
+	static boost::signals2::signal<void(PBD::Controllable*)> StopLearning;
 
-	static sigc::signal<void,Controllable*> Destroyed;
-
-	sigc::signal<void> Changed;
+	static boost::signals2::signal<void(Controllable*)> Destroyed;
+	
+	boost::signals2::signal<void()> Changed;
 
 	int set_state (const XMLNode&, int version);
 	XMLNode& get_state ();
@@ -73,8 +72,8 @@ class Controllable : public PBD::StatefulDestructible {
 	std::string _uri;
 	bool        _touching;
 
-	void add ();
-	void remove ();
+	static void add (Controllable&);
+	static void remove (Controllable&);
 
 	typedef std::set<PBD::Controllable*> Controllables;
 	typedef std::map<std::string,PBD::Controllable*> ControllablesByURI;
diff --git a/libs/pbd/pbd/destructible.h b/libs/pbd/pbd/destructible.h
index 827feb8fe5..241d847aff 100644
--- a/libs/pbd/pbd/destructible.h
+++ b/libs/pbd/pbd/destructible.h
@@ -20,26 +20,20 @@
 #ifndef __pbd_destructible_h__
 #define __pbd_destructible_h__
 
-#include <sigc++/signal.h>
+#include <boost/signals2.hpp>
 
 namespace PBD {
 
-/* be very very careful using this class. it does not inherit from sigc::trackable and thus
-   should only be used in multiple-inheritance situations involving another type
-   that does inherit from sigc::trackable (or sigc::trackable itself)
-*/
-
-class ThingWithGoingAway {
-  public:
-	virtual ~ThingWithGoingAway () {}
-	sigc::signal<void> GoingAway;
-};
-
-class Destructible : public sigc::trackable, public ThingWithGoingAway {
+class Destructible {
   public:
+        Destructible() : refs_dropped (false){}
 	virtual ~Destructible () {}
-	void drop_references () const { GoingAway(); }
+	
+	boost::signals2::signal<void ()> GoingAway;
+	void drop_references () { if (!refs_dropped) { GoingAway(); } refs_dropped = true; }
 
+  private:
+	bool refs_dropped;
 };
 
 }
diff --git a/libs/pbd/pbd/memento_command.h b/libs/pbd/pbd/memento_command.h
index c1e5d75f9c..c5e8b19272 100644
--- a/libs/pbd/pbd/memento_command.h
+++ b/libs/pbd/pbd/memento_command.h
@@ -26,7 +26,6 @@
 #include "pbd/command.h"
 #include "pbd/stacktrace.h"
 #include "pbd/xml++.h"
-#include "pbd/shiva.h"
 
 #include <sigc++/slot.h>
 #include <typeinfo>
@@ -42,16 +41,20 @@ public:
 	MementoCommand(obj_T& a_object, XMLNode* a_before, XMLNode* a_after) 
 		: obj(a_object), before(a_before), after(a_after)
 	{
-		/* catch destruction of the object */
-		new PBD::PairedShiva< obj_T,MementoCommand<obj_T> > (obj, *this);
+		/* if the object dies, make sure that we die and that everyone knows about it */
+		obj_death_connection = obj.GoingAway.connect (boost::bind (&MementoCommand::object_died, this));
 	}
 
 	~MementoCommand () {
-		GoingAway(); /* EMIT SIGNAL */
+		drop_references ();
 		delete before;
 		delete after;
 	}
 
+	void object_died () {
+		delete this;
+	}
+
 	void operator() () {
 		if (after) {
 			obj.set_state(*after, Stateful::current_state_version); 
@@ -94,6 +97,7 @@ protected:
 	obj_T&   obj;
 	XMLNode* before;
 	XMLNode* after;
+	boost::signals2::scoped_connection obj_death_connection;
 };
 
 #endif // __lib_pbd_memento_h__
diff --git a/libs/pbd/pbd/statefuldestructible.h b/libs/pbd/pbd/statefuldestructible.h
index 49a33ff438..36eb43147c 100644
--- a/libs/pbd/pbd/statefuldestructible.h
+++ b/libs/pbd/pbd/statefuldestructible.h
@@ -29,16 +29,6 @@ class StatefulDestructible : public Stateful, public Destructible
 {
 };
 
-/* be very very careful using this class. it does not inherit from sigc::trackable and thus
-   should only be used in multiple-inheritance situations involving another type
-   that does inherit from sigc::trackable (or sigc::trackable itself)
-*/
-
-class StatefulThingWithGoingAway : public Stateful, public ThingWithGoingAway
-{
-};
-
 }
 
-
 #endif /* __pbd_stateful_destructible_h__ */
diff --git a/libs/pbd/pbd/undo.h b/libs/pbd/pbd/undo.h
index 0e48bea962..6340ef04b9 100644
--- a/libs/pbd/pbd/undo.h
+++ b/libs/pbd/pbd/undo.h
@@ -26,12 +26,13 @@
 #include <sigc++/slot.h>
 #include <sigc++/bind.h>
 #include <sys/time.h>
+
+#include "pbd/scoped_connections.h"
 #include "pbd/command.h"
-#include "pbd/shiva.h"
 
 typedef sigc::slot<void> UndoAction;
 
-class UndoTransaction : public Command
+class UndoTransaction : public Command, public PBD::ScopedConnectionList
 {
   public:
 	UndoTransaction ();
@@ -61,7 +62,6 @@ class UndoTransaction : public Command
 
   private:
 	std::list<Command*>    actions;
-	std::list<PBD::ProxyShiva<Command,UndoTransaction>*> shivas;
 	struct timeval        _timestamp;
 	bool                  _clearing;
 
@@ -71,10 +71,9 @@ class UndoTransaction : public Command
 
 	~UndoTransaction ();
 	void about_to_explicitly_delete ();
-	
 };
 
-class UndoHistory : public sigc::trackable
+class UndoHistory : public PBD::ScopedConnectionList
 {
   public:
 	UndoHistory();
@@ -107,7 +106,7 @@ class UndoHistory : public sigc::trackable
 
 	void set_depth (uint32_t);
 
-	sigc::signal<void> Changed;
+	boost::signals2::signal<void()> Changed;
 	
   private:
 	bool _clearing;
diff --git a/libs/pbd/stateful.cc b/libs/pbd/stateful.cc
index 58be141a27..596402576e 100644
--- a/libs/pbd/stateful.cc
+++ b/libs/pbd/stateful.cc
@@ -21,6 +21,7 @@
 #include <unistd.h>
 
 #include "pbd/stateful.h"
+#include "pbd/destructible.h"
 #include "pbd/filesystem.h"
 #include "pbd/xml++.h"
 #include "pbd/error.h"
diff --git a/libs/pbd/undo.cc b/libs/pbd/undo.cc
index a0e98f9a13..78c16291b7 100644
--- a/libs/pbd/undo.cc
+++ b/libs/pbd/undo.cc
@@ -46,7 +46,7 @@ UndoTransaction::UndoTransaction (const UndoTransaction& rhs)
 
 UndoTransaction::~UndoTransaction ()
 {
-	GoingAway ();
+	drop_references ();
 	clear ();
 }
 
@@ -78,9 +78,11 @@ void
 UndoTransaction::add_command (Command *const action)
 {
 	/* catch death of command (e.g. caused by death of object to
-	   which it refers.
+	   which it refers. command_death() is a normal static function
+	   so there is no need to manage this connection.
 	 */
-	shivas.push_back (new PBD::ProxyShiva<Command,UndoTransaction> (*action, *this, &command_death));
+
+	scoped_connect (action->GoingAway, boost::bind (&command_death, this, action));
 	actions.push_back (action);
 }
 
@@ -90,21 +92,6 @@ UndoTransaction::remove_command (Command* const action)
 	actions.remove (action);
 }
 
-void
-UndoTransaction::about_to_explicitly_delete ()
-{
-	/* someone is going to call our destructor and its not Shiva,
-	   the god of destruction and chaos. This happens when an UndoHistory
-	   is pruning itself. we must remove Shivas to avoid the god
-	   striking us down a second time, unnecessarily and illegally.
-	*/
-
-	for (list<PBD::ProxyShiva<Command,UndoTransaction>*>::iterator i = shivas.begin(); i != shivas.end(); ++i) {
-		delete *i;
-	}
-	shivas.clear ();
-}
-
 bool
 UndoTransaction::empty () const
 {
@@ -188,7 +175,6 @@ UndoHistory::set_depth (uint32_t d)
 		while (cnt--) {
 			ut = UndoList.front();
 			UndoList.pop_front ();
-			ut->about_to_explicitly_delete ();
 			delete ut;
 		}
 	}
@@ -199,7 +185,7 @@ UndoHistory::add (UndoTransaction* const ut)
 {
 	uint32_t current_depth = UndoList.size();
 
-	ut->GoingAway.connect (bind (mem_fun (*this, &UndoHistory::remove), ut));
+	scoped_connect (ut->GoingAway, boost::bind (&UndoHistory::remove, this, ut));
 
 	/* if the current undo history is larger than or equal to the currently
 	   requested depth, then pop off at least 1 element to make space
@@ -214,7 +200,6 @@ UndoHistory::add (UndoTransaction* const ut)
 			UndoTransaction* ut;
 			ut = UndoList.front ();
 			UndoList.pop_front ();
-			ut->about_to_explicitly_delete ();
 			delete ut;
 		}
 	}
diff --git a/libs/pbd/wscript b/libs/pbd/wscript
index 84c18cc899..aacbd990ad 100644
--- a/libs/pbd/wscript
+++ b/libs/pbd/wscript
@@ -73,6 +73,7 @@ def build(bld):
 		pool.cc
 		pthread_utils.cc
 		receiver.cc
+		scoped_connections.cc
 		search_path.cc
 		shortpath.cc
 		stacktrace.cc
diff --git a/libs/surfaces/generic_midi/generic_midi_control_protocol.cc b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
index 097dbc3aec..a20835dc05 100644
--- a/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
+++ b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
@@ -175,11 +175,13 @@ GenericMidiControlProtocol::start_learning (Controllable* c)
 	{
 		Glib::Mutex::Lock lm (pending_lock);
 
-		std::pair<MIDIControllable *, sigc::connection> element;
+#if 0 // BOOST SIGNALS
+		std::pair<MIDIControllable *, boost::signals2::scoped_connection> element;
 		element.first = mc;
 		element.second = c->LearningFinished.connect (bind (mem_fun (*this, &GenericMidiControlProtocol::learning_stopped), mc));
 
 		pending_controllables.push_back (element);
+#endif
 	}
 
 	mc->learn_about_external_control ();
diff --git a/libs/surfaces/generic_midi/midicontrollable.cc b/libs/surfaces/generic_midi/midicontrollable.cc
index 124ef95615..533bb6db21 100644
--- a/libs/surfaces/generic_midi/midicontrollable.cc
+++ b/libs/surfaces/generic_midi/midicontrollable.cc
@@ -27,7 +27,6 @@
 
 #include "midicontrollable.h"
 
-using namespace sigc;
 using namespace std;
 using namespace MIDI;
 using namespace PBD;
@@ -110,7 +109,7 @@ void
 MIDIControllable::learn_about_external_control ()
 {
 	drop_external_control ();
-	midi_learn_connection = _port.input()->any.connect (mem_fun (*this, &MIDIControllable::midi_receiver));
+	midi_learn_connection = _port.input()->any.connect (boost::bind (&MIDIControllable::midi_receiver, this, _1, _2, _3));
 }
 
 void
@@ -302,7 +301,7 @@ MIDIControllable::bind_midi (channel_t chn, eventType ev, MIDI::byte additional)
 	switch (ev) {
 	case MIDI::off:
 		midi_sense_connection[0] = p.channel_note_off[chn_i].connect
-			(mem_fun (*this, &MIDIControllable::midi_sense_note_off));
+			(boost::bind (&MIDIControllable::midi_sense_note_off, this, _1, _2));
 
 		/* if this is a bistate, connect to noteOn as well,
 		   and we'll toggle back and forth between the two.
@@ -310,7 +309,7 @@ MIDIControllable::bind_midi (channel_t chn, eventType ev, MIDI::byte additional)
 
 		if (bistate) {
 			midi_sense_connection[1] = p.channel_note_on[chn_i].connect
-				(mem_fun (*this, &MIDIControllable::midi_sense_note_on));
+				(boost::bind (&MIDIControllable::midi_sense_note_on, this, _1, _2));
 			connections = 2;
 		} else {
 			connections = 1;
@@ -320,20 +319,20 @@ MIDIControllable::bind_midi (channel_t chn, eventType ev, MIDI::byte additional)
 
 	case MIDI::on:
 		midi_sense_connection[0] = p.channel_note_on[chn_i].connect
-			(mem_fun (*this, &MIDIControllable::midi_sense_note_on));
+			(boost::bind (&MIDIControllable::midi_sense_note_on, this, _1, _2));
 		if (bistate) {
 			midi_sense_connection[1] = p.channel_note_off[chn_i].connect
-				(mem_fun (*this, &MIDIControllable::midi_sense_note_off));
+				(boost::bind (&MIDIControllable::midi_sense_note_off, this, _1, _2));
 			connections = 2;
 		} else {
 			connections = 1;
 		}
 		_control_description = "MIDI control: NoteOn";
 		break;
-
+		
 	case MIDI::controller:
 		midi_sense_connection[0] = p.channel_controller[chn_i].connect
-			(mem_fun (*this, &MIDIControllable::midi_sense_controller));
+			(boost::bind (&MIDIControllable::midi_sense_controller, this, _1, _2));
 		connections = 1;
 		snprintf (buf, sizeof (buf), "MIDI control: Controller %d", control_additional);
 		_control_description = buf;
@@ -342,8 +341,7 @@ MIDIControllable::bind_midi (channel_t chn, eventType ev, MIDI::byte additional)
 	case MIDI::program:
 		if (!bistate) {
 			midi_sense_connection[0] = p.channel_program_change[chn_i].connect
-				(mem_fun (*this,
-				       &MIDIControllable::midi_sense_program_change));
+				(boost::bind (&MIDIControllable::midi_sense_program_change, this, _1, _2));
 			connections = 1;
 			_control_description = "MIDI control: ProgramChange";
 		}
@@ -352,7 +350,7 @@ MIDIControllable::bind_midi (channel_t chn, eventType ev, MIDI::byte additional)
 	case MIDI::pitchbend:
 		if (!bistate) {
 			midi_sense_connection[0] = p.channel_pitchbend[chn_i].connect
-				(mem_fun (*this, &MIDIControllable::midi_sense_pitchbend));
+				(boost::bind (&MIDIControllable::midi_sense_pitchbend, this, _1, _2));
 			connections = 1;
 			_control_description = "MIDI control: Pitchbend";
 		}
diff --git a/libs/surfaces/generic_midi/midicontrollable.h b/libs/surfaces/generic_midi/midicontrollable.h
index a9a40944d8..cc85cc42c1 100644
--- a/libs/surfaces/generic_midi/midicontrollable.h
+++ b/libs/surfaces/generic_midi/midicontrollable.h
@@ -22,7 +22,7 @@
 
 #include <string>
 
-#include <sigc++/sigc++.h>
+#include <boost/signals2.hpp>
 
 #include "midi++/types.h"
 #include "pbd/controllable.h"
@@ -82,8 +82,8 @@ class MIDIControllable : public PBD::Stateful
 	MIDI::byte       last_value;
 	bool             bistate;
 	int              midi_msg_id;      /* controller ID or note number */
-	sigc::connection midi_sense_connection[2];
-	sigc::connection midi_learn_connection;
+	boost::signals2::connection midi_sense_connection[2];
+	boost::signals2::connection midi_learn_connection;
 	size_t           connections;
 	MIDI::eventType  control_type;
 	MIDI::byte       control_additional;
diff --git a/libs/surfaces/mackie/controls.h b/libs/surfaces/mackie/controls.h
index 84283f3016..acd91e6047 100644
--- a/libs/surfaces/mackie/controls.h
+++ b/libs/surfaces/mackie/controls.h
@@ -18,12 +18,12 @@
 #ifndef mackie_controls_h
 #define mackie_controls_h
 
-#include <sigc++/sigc++.h>
-
 #include <map>
 #include <vector>
 #include <string>
 
+#include <boost/signals2.hpp>
+
 #include "mackie_control_exception.h"
 
 namespace Mackie
@@ -228,7 +228,7 @@ public:
 	virtual unsigned int in_use_timeout() { return _in_use_timeout; }
 
 	/// Keep track of the timeout so it can be updated with more incoming events
-	sigc::connection in_use_connection;
+	boost::signals2::scoped_connection in_use_connection;
 	
 private:
 	int _id;
diff --git a/libs/surfaces/mackie/mackie_control_protocol.cc b/libs/surfaces/mackie/mackie_control_protocol.cc
index 6e65308f33..7460b041ad 100644
--- a/libs/surfaces/mackie/mackie_control_protocol.cc
+++ b/libs/surfaces/mackie/mackie_control_protocol.cc
@@ -61,7 +61,6 @@
 
 using namespace ARDOUR;
 using namespace std;
-using namespace sigc;
 using namespace Mackie;
 using namespace PBD;
 
@@ -74,7 +73,6 @@ MackieMidiBuilder builder;
 MackieControlProtocol::MackieControlProtocol (Session& session)
 	: ControlProtocol  (session, X_("Mackie"))
 	, _current_initial_bank( 0 )
-	, connections_back( _connections )
 	, _surface( 0 )
 	, _ports_changed( false )
 	, _polling( true )
@@ -564,23 +562,23 @@ void MackieControlProtocol::update_surface()
 void MackieControlProtocol::connect_session_signals()
 {
 	// receive routes added
-	connections_back = session->RouteAdded.connect( ( mem_fun (*this, &MackieControlProtocol::notify_route_added) ) );
+	session_connections.add_connection (session->RouteAdded.connect(boost::bind (&MackieControlProtocol::notify_route_added, this, _1)));
 	// receive record state toggled
-	connections_back = session->RecordStateChanged.connect( ( mem_fun (*this, &MackieControlProtocol::notify_record_state_changed) ) );
+	session_connections.add_connection (session->RecordStateChanged.connect(boost::bind (&MackieControlProtocol::notify_record_state_changed, this)));
 	// receive transport state changed
-	connections_back = session->TransportStateChange.connect( ( mem_fun (*this, &MackieControlProtocol::notify_transport_state_changed) ) );
+	session_connections.add_connection (session->TransportStateChange.connect(boost::bind (&MackieControlProtocol::notify_transport_state_changed, this)));
 	// receive punch-in and punch-out
-	connections_back = Config->ParameterChanged.connect( ( mem_fun (*this, &MackieControlProtocol::notify_parameter_changed) ) );
-	session->config.ParameterChanged.connect ( ( mem_fun (*this, &MackieControlProtocol::notify_parameter_changed) ) );
+	session_connections.add_connection (Config->ParameterChanged.connect(boost::bind (&MackieControlProtocol::notify_parameter_changed, this, _1)));
+	session_connections.add_connection (session->config.ParameterChanged.connect (boost::bind (&MackieControlProtocol::notify_parameter_changed, this, _1)));
 	// receive rude solo changed
-	connections_back = session->SoloActive.connect( ( mem_fun (*this, &MackieControlProtocol::notify_solo_active_changed) ) );
+	session_connections.add_connection (session->SoloActive.connect(boost::bind (&MackieControlProtocol::notify_solo_active_changed, this, _1)));
 
 	// make sure remote id changed signals reach here
 	// see also notify_route_added
 	Sorted sorted = get_sorted_routes();
 	for ( Sorted::iterator it = sorted.begin(); it != sorted.end(); ++it )
 	{
-		connections_back = (*it)->RemoteControlIDChanged.connect( ( mem_fun (*this, &MackieControlProtocol::notify_remote_id_changed) ) );
+		session_connections.add_connection ((*it)->RemoteControlIDChanged.connect (boost::bind(&MackieControlProtocol::notify_remote_id_changed, this)));
 	}
 }
 
@@ -603,27 +601,10 @@ void MackieControlProtocol::add_port( MIDI::Port & midi_port, int number )
 	{
 		MackiePort * sport = new MackiePort( *this, midi_port, number );
 		_ports.push_back( sport );
-
-		connections_back = sport->init_event.connect(
-			sigc::bind (
-				mem_fun (*this, &MackieControlProtocol::handle_port_init)
-				, sport
-			)
-		);
-
-		connections_back = sport->active_event.connect(
-			sigc::bind (
-				mem_fun (*this, &MackieControlProtocol::handle_port_active)
-				, sport
-			)
-		);
-
-		connections_back = sport->inactive_event.connect(
-			sigc::bind (
-				mem_fun (*this, &MackieControlProtocol::handle_port_inactive)
-				, sport
-			)
-		);
+		
+		port_connections.add_connection (sport->init_event.connect (boost::bind (&MackieControlProtocol::handle_port_init, this, sport)));
+		port_connections.add_connection (sport->active_event.connect (boost::bind (&MackieControlProtocol::handle_port_active, this, sport)));
+		port_connections.add_connection (sport->inactive_event.connect (boost::bind (&MackieControlProtocol::handle_port_inactive, this, sport)));
 
 		_ports_changed = true;
 	}
@@ -699,9 +680,9 @@ void MackieControlProtocol::initialize_surface()
 	_surface->init();
 
 	// Connect events. Must be after route table otherwise there will be trouble
-	for( MackiePorts::iterator it = _ports.begin(); it != _ports.end(); ++it )
-	{
-		connections_back = (*it)->control_event.connect( ( mem_fun (*this, &MackieControlProtocol::handle_control_event) ) );
+
+	for( MackiePorts::iterator it = _ports.begin(); it != _ports.end(); ++it ) {
+		port_connections.add_connection ((*it)->control_event.connect(boost::bind (&MackieControlProtocol::handle_control_event, this, _1, _2, _3)));
 	}
 }
 
@@ -713,18 +694,9 @@ void MackieControlProtocol::close()
 	_polling = false;
 	pthread_join( thread, 0 );
 
-	// TODO disconnect port active/inactive signals
-	// Or at least put a lock here
-
-	// disconnect global signals from Session
-	// TODO Since *this is a sigc::trackable, this shouldn't be necessary
-	// but it is for some reason
-#if 0
-	for( vector<sigc::connection>::iterator it = _connections.begin(); it != _connections.end(); ++it )
-	{
-		it->disconnect();
-	}
-#endif
+	port_connections.drop_connections ();
+	session_connections.drop_connections ();
+	route_connections.drop_connections ();
 
 	if ( _surface != 0 )
 	{
@@ -1471,9 +1443,9 @@ void MackieControlProtocol::notify_route_added( ARDOUR::RouteList & rl )
 
 	// make sure remote id changes in the new route are handled
 	typedef ARDOUR::RouteList ARS;
-	for ( ARS::iterator it = rl.begin(); it != rl.end(); ++it )
-	{
-		connections_back = (*it)->RemoteControlIDChanged.connect( ( mem_fun (*this, &MackieControlProtocol::notify_remote_id_changed) ) );
+
+	for (ARS::iterator it = rl.begin(); it != rl.end(); ++it) {
+		route_connections.add_connection ((*it)->RemoteControlIDChanged.connect (boost::bind (&MackieControlProtocol::notify_remote_id_changed, this)));
 	}
 }
 
diff --git a/libs/surfaces/mackie/mackie_control_protocol.h b/libs/surfaces/mackie/mackie_control_protocol.h
index d220213d2d..58d05f7b7f 100644
--- a/libs/surfaces/mackie/mackie_control_protocol.h
+++ b/libs/surfaces/mackie/mackie_control_protocol.h
@@ -335,12 +335,12 @@ class MackieControlProtocol
   
 	/// Protects set_active, and allows waiting on the poll thread
 	Glib::Cond update_cond;
-
-	// because sigc::trackable doesn't seem to be working
-	std::vector<sigc::connection> _connections;
-	std::back_insert_iterator<std::vector<sigc::connection> > connections_back;
-
-   /// The representation of the physical controls on the surface.
+	
+	PBD::ScopedConnectionList session_connections;
+	PBD::ScopedConnectionList port_connections;
+	PBD::ScopedConnectionList route_connections;
+	
+	/// The representation of the physical controls on the surface.
   	Mackie::Surface * _surface;
 	
 	/// If a port is opened or closed, this will be
diff --git a/libs/surfaces/mackie/mackie_port.cc b/libs/surfaces/mackie/mackie_port.cc
index 4413d3fc34..3316483914 100644
--- a/libs/surfaces/mackie/mackie_port.cc
+++ b/libs/surfaces/mackie/mackie_port.cc
@@ -29,7 +29,6 @@
 
 #include "midi++/types.h"
 #include "midi++/port.h"
-#include "sigc++/sigc++.h"
 #include "ardour/rc_configuration.h"
 
 #include "i18n.h"
@@ -95,7 +94,7 @@ void MackiePort::open()
 #ifdef PORT_DEBUG
 	cout << "MackiePort::open " << *this << endl;
 #endif
-	_sysex = port().input()->sysex.connect( ( mem_fun (*this, &MackiePort::handle_midi_sysex) ) );
+	_sysex = port().input()->sysex.connect (boost::bind (&MackiePort::handle_midi_sysex, this, _1, _2, _3));
 	
 	// make sure the device is connected
 	init();
@@ -301,7 +300,7 @@ void MackiePort::connect_any()
 #ifdef DEBUG
 		cout << "connect input parser " << port().input() << " to handle_midi_any" << endl;
 #endif
-		_any = port().input()->any.connect( mem_fun( *this, &MackiePort::handle_midi_any ) );
+		_any = port().input()->any.connect (boost::bind (&MackiePort::handle_midi_any, this, _1, _2, _3));
 #ifdef DEBUG
 		cout << "input parser any connections: " << port().input()->any.size() << endl;
 #endif
@@ -503,8 +502,9 @@ void MackiePort::handle_midi_any (MIDI::Parser &, MIDI::byte * raw_bytes, size_t
 				// first disconnect any previous timeouts
 				control.in_use_connection.disconnect();
 				
+#if 0 // BOOSTSIGNALS
 				// now connect a new timeout to call handle_control_timeout_event
-				sigc::slot<bool> timeout_slot = sigc::bind(
+				sigc::slot<bool> timeout_slot = sigc::bind (
 					mem_fun( *this, &MackiePort::handle_control_timeout_event )
 					, &control
 				);
@@ -512,7 +512,7 @@ void MackiePort::handle_midi_any (MIDI::Parser &, MIDI::byte * raw_bytes, size_t
 					timeout_slot
 					, control.in_use_timeout()
 				);
-				
+#endif				
 				// emit the control event
 				control_event( *this, control, state );
 				break;
diff --git a/libs/surfaces/mackie/mackie_port.h b/libs/surfaces/mackie/mackie_port.h
index 26ec1ca799..639183d066 100644
--- a/libs/surfaces/mackie/mackie_port.h
+++ b/libs/surfaces/mackie/mackie_port.h
@@ -21,8 +21,7 @@
 #include "surface_port.h"
 
 #include <midi++/types.h>
-#include <sigc++/signal.h>
-#include <sigc++/connection.h>
+#include <boost/signals2.hpp>
 
 #include <glibmm/thread.h>
 
@@ -116,8 +115,8 @@ protected:
 private:
 	MackieControlProtocol & _mcp;
 	port_type_t _port_type;
-	sigc::connection _any;
-	sigc::connection _sysex;
+	boost::signals2::scoped_connection _any;
+	boost::signals2::scoped_connection _sysex;
 	emulation_t _emulation;
 
 	bool _initialising;
diff --git a/libs/surfaces/mackie/route_signal.cc b/libs/surfaces/mackie/route_signal.cc
index af99e5d91b..fb6cf5b092 100644
--- a/libs/surfaces/mackie/route_signal.cc
+++ b/libs/surfaces/mackie/route_signal.cc
@@ -31,34 +31,36 @@ using namespace std;
 
 void RouteSignal::connect()
 {
-	back_insert_iterator<Connections> cins = back_inserter( _connections );
+	if (_strip.has_solo()) {
+		connections.add_connection (_route->solo_control()->Changed.connect(boost::bind (&MackieControlProtocol::notify_solo_changed, &_mcp, this)));
+	}
 
-	if ( _strip.has_solo() )
-		cins = _route->solo_control()->Changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_solo_changed ), this ) );
-	
-	if ( _strip.has_mute() )
-		cins = _route->mute_control()->Changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_mute_changed ), this ) );
-	
-	if ( _strip.has_gain() )
-		cins = _route->gain_control()->Changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_gain_changed ), this, true ) );
-		
-	cins = _route->NameChanged.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_name_changed ), this ) );
+	if (_strip.has_mute()) {
+		connections.add_connection (_route->mute_control()->Changed.connect(boost::bind (&MackieControlProtocol::notify_mute_changed, &_mcp, this)));
+	}
+
+	if (_strip.has_gain()) {
+		connections.add_connection (_route->gain_control()->Changed.connect(boost::bind (&MackieControlProtocol::notify_gain_changed, &_mcp, this, false)));
+	}
+
+	connections.add_connection (_route->NameChanged.connect (boost::bind (&MackieControlProtocol::notify_name_changed, &_mcp, this)));
 	
 	if (_route->panner()) {
-		cins = _route->panner()->Changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_panner_changed ), this, true ) );
+		connections.add_connection (_route->panner()->Changed.connect(boost::bind (&MackieControlProtocol::notify_panner_changed, &_mcp, this, false)));
+		
 		for ( unsigned int i = 0; i < _route->panner()->npanners(); ++i ) {
-			cins = _route->panner()->streampanner (i).Changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_panner_changed ), this, true ) );
+			connections.add_connection (_route->panner()->streampanner(i).Changed.connect (boost::bind (&MackieControlProtocol::notify_panner_changed, &_mcp, this, false)));
 		}
 	}
 	
 	boost::shared_ptr<Track> trk = boost::dynamic_pointer_cast<ARDOUR::Track>(_route);
 	if (trk) {
-		cins = trk->rec_enable_control()->Changed .connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_record_enable_changed ), this));
+		connections.add_connection (trk->rec_enable_control()->Changed .connect(boost::bind (&MackieControlProtocol::notify_record_enable_changed, &_mcp, this)));
 	}
 	
 	// TODO this works when a currently-banked route is made inactive, but not
 	// when a route is activated which should be currently banked.
-	cins = _route->active_changed.connect( sigc::bind ( mem_fun ( _mcp, &MackieControlProtocol::notify_active_changed ), this ) );
+	connections.add_connection (_route->active_changed.connect (boost::bind (&MackieControlProtocol::notify_active_changed, &_mcp, this)));
 
 	// TODO
 	// SelectedChanged
@@ -67,10 +69,7 @@ void RouteSignal::connect()
 
 void RouteSignal::disconnect()
 {
-	for ( Connections::iterator it = _connections.begin(); it != _connections.end(); ++it )
-	{
-		it->disconnect();
-	}
+	connections.drop_connections ();
 }
 
 void RouteSignal::notify_all()
diff --git a/libs/surfaces/mackie/route_signal.h b/libs/surfaces/mackie/route_signal.h
index a272449e52..5b388a7da5 100644
--- a/libs/surfaces/mackie/route_signal.h
+++ b/libs/surfaces/mackie/route_signal.h
@@ -18,10 +18,10 @@
 #ifndef route_signal_h
 #define route_signal_h
 
-#include <sigc++/sigc++.h>
+#include <vector>
 #include <boost/shared_ptr.hpp>
 
-#include <vector>
+#include "pbd/scoped_connections.h"
 
 #include "midi_byte_array.h"
 
@@ -79,8 +79,7 @@ private:
 	Strip & _strip;
 	SurfacePort & _port;
 
-	typedef std::vector<sigc::connection> Connections;
-	Connections _connections;
+	PBD::ScopedConnectionList connections;
 
 	// Last written values for the gain and pan, to avoid overloading
 	// the midi connection to the surface
diff --git a/libs/surfaces/mackie/surface_port.h b/libs/surfaces/mackie/surface_port.h
index 421446df68..f41f2865bb 100644
--- a/libs/surfaces/mackie/surface_port.h
+++ b/libs/surfaces/mackie/surface_port.h
@@ -18,7 +18,7 @@
 #ifndef surface_port_h
 #define surface_port_h
 
-#include <sigc++/signal.h>
+#include <boost/signals2.hpp>
 #include <glibmm/thread.h>
 
 #include "midi_byte_array.h"
@@ -34,7 +34,7 @@ namespace Mackie
 /**
 	Make a relationship between a midi port and a Mackie device.
 */
-class SurfacePort : public sigc::trackable
+class SurfacePort
 {
 public:
 	SurfacePort( MIDI::Port & port, int number );
@@ -64,19 +64,19 @@ public:
 	const MIDI::Port & port() const { return *_port; }
 	
 	// all control notofications are sent from here
-	sigc::signal<void, SurfacePort &, Control &, const ControlState &> control_event;
+	boost::signals2::signal<void(SurfacePort &, Control &, const ControlState &)> control_event;
 	
 	// emitted just before the port goes into initialisation
 	// where it tries to establish that its device is connected
-	sigc::signal<void> init_event;
+	boost::signals2::signal<void()> init_event;
 	
 	// emitted when the port completes initialisation successfully
-	sigc::signal<void> active_event;
+	boost::signals2::signal<void()> active_event;
 
 	// emitted when the port goes inactive (ie a read or write failed)
-	sigc::signal<void> inactive_event;
+	boost::signals2::signal<void()> inactive_event;
 	
-	// the port number - master is 0, extenders are 1,2,3,4
+	// the port number - master is 0(extenders are 1((,4
 	virtual int number() const { return _number; }
 	
 	// number of strips handled by this port. Usually 8.
diff --git a/libs/surfaces/osc/osc.cc b/libs/surfaces/osc/osc.cc
index 4a151d44d0..931a5c1a58 100644
--- a/libs/surfaces/osc/osc.cc
+++ b/libs/surfaces/osc/osc.cc
@@ -29,6 +29,7 @@
 #include <fcntl.h>
 
 #include <glibmm/miscutils.h>
+#include <boost/signals2.hpp>
 
 #include <pbd/pthread_utils.h>
 #include <pbd/file_utils.h>
@@ -82,7 +83,7 @@ OSC::OSC (Session& s, uint32_t port)
 
 	// "Application Hooks"
 	session_loaded (s);
-	session->Exported.connect (sigc::mem_fun (*this, &OSC::session_exported));
+	scoped_connect (session->Exported, boost::bind (&OSC::session_exported, this, _1, _2));
 }
 
 OSC::~OSC()
@@ -572,7 +573,7 @@ OSC::listen_to_route (boost::shared_ptr<Route> route, lo_address addr)
 	*/
 	
 	if (!route_exists) {
-		route->GoingAway.connect (sigc::bind (sigc::mem_fun (*this, &OSC::drop_route), boost::weak_ptr<Route> (route)));
+		scoped_connect (route->GoingAway, (boost::bind (&OSC::drop_route, this, boost::weak_ptr<Route> (route))));
 	}
 }
 
diff --git a/libs/surfaces/osc/osc.h b/libs/surfaces/osc/osc.h
index c0be2c0b18..314d37c7bd 100644
--- a/libs/surfaces/osc/osc.h
+++ b/libs/surfaces/osc/osc.h
@@ -31,9 +31,8 @@
 
 #include <glibmm/main.h>
 
-#include <sigc++/sigc++.h>
-
 #include "pbd/abstract_ui.h"
+#include "pbd/scoped_connections.h"
 
 #include "ardour/types.h"
 #include "control_protocol/control_protocol.h"
@@ -56,7 +55,7 @@ struct OSCUIRequest : public BaseUI::BaseRequestObject {
 	~OSCUIRequest() {}
 };
 
-class OSC : public ARDOUR::ControlProtocol, public AbstractUI<OSCUIRequest>
+class OSC : public ARDOUR::ControlProtocol, public PBD::ScopedConnectionList, public AbstractUI<OSCUIRequest>
 {
   public:
 	OSC (ARDOUR::Session&, uint32_t port);