diff --git a/src/gui/gtk-lumiera.hpp b/src/gui/gtk-lumiera.hpp
index a25927712..e86e44fbd 100644
--- a/src/gui/gtk-lumiera.hpp
+++ b/src/gui/gtk-lumiera.hpp
@@ -32,6 +32,7 @@
 #include <nobug.h>
 #include <vector>
 #include <boost/utility.hpp>
+#include <boost/shared_ptr.hpp>
 
 extern "C" {
 #include <gavl/gavltime.h>
diff --git a/src/gui/model/project.cpp b/src/gui/model/project.cpp
index 25ab3f964..843351cc3 100644
--- a/src/gui/model/project.cpp
+++ b/src/gui/model/project.cpp
@@ -25,6 +25,9 @@
 #include "project.hpp"
 #include "sequence.hpp"
 
+using namespace std;
+using namespace boost;
+
 namespace gui {
 namespace model {
 
@@ -37,11 +40,10 @@ Project::Project()
 
 Project::~Project()
 {
-  BOOST_FOREACH( Sequence* const sequence, sequences )
-    delete sequence;    
+
 }
 
-const std::list<Sequence*>&
+const std::list< shared_ptr<Sequence> >&
 Project::get_sequences()
 {
   return sequences;
@@ -50,7 +52,7 @@ Project::get_sequences()
 void
 Project::add_new_sequence(Glib::ustring name)
 {
-  Sequence* const sequence = new Sequence();
+  shared_ptr<Sequence> sequence(new Sequence());
   sequence->set_name(name);
   sequences.push_back(sequence);
   sequenceListChangedSignal.emit();
diff --git a/src/gui/model/project.hpp b/src/gui/model/project.hpp
index 1bd7a7f4a..cb7945204 100644
--- a/src/gui/model/project.hpp
+++ b/src/gui/model/project.hpp
@@ -39,7 +39,7 @@ public:
   
   ~Project();
     
-  const std::list<Sequence*>& get_sequences();
+  const std::list< boost::shared_ptr<Sequence> >& get_sequences();
   
   void add_new_sequence(Glib::ustring name);
   
@@ -48,7 +48,7 @@ public:
   
 private:
 
-  std::list<Sequence*> sequences;
+  std::list< boost::shared_ptr<Sequence> > sequences;
   
   sigc::signal<void> sequenceListChangedSignal;
 };
diff --git a/src/gui/panels/timeline-panel.cpp b/src/gui/panels/timeline-panel.cpp
index a64b97e34..94c07cc02 100644
--- a/src/gui/panels/timeline-panel.cpp
+++ b/src/gui/panels/timeline-panel.cpp
@@ -34,6 +34,7 @@ extern "C" {
 using namespace Gtk;
 using namespace sigc;
 using namespace std;
+using namespace boost;
 using namespace gui::widgets;
 using namespace gui::model;
 
@@ -114,7 +115,7 @@ TimelinePanel::TimelinePanel(model::Project *const owner_project) :
 TimelinePanel::~TimelinePanel()
 {
   // Free allocated widgets
-  pair<model::Sequence*, TimelineWidget*> pair; 
+  pair<const model::Sequence*, TimelineWidget*> pair; 
   BOOST_FOREACH( pair, notebook_pages )
     delete pair.second;
 }
@@ -220,13 +221,15 @@ TimelinePanel::on_sequence_list_changed()
 void
 TimelinePanel::update_notebook()
 {
-  std::map<Sequence*, TimelineWidget*> old_pages(notebook_pages);
+  std::map<const model::Sequence*, TimelineWidget*>
+    old_pages(notebook_pages);
   notebook_pages.clear();
-  
-  BOOST_FOREACH( Sequence* const sequence, project->get_sequences() )
+
+  BOOST_FOREACH( boost::shared_ptr< model::Sequence > sequence,
+    project->get_sequences() )
     {
-      std::map<Sequence*, TimelineWidget*>::iterator iterator =
-        old_pages.find(sequence);
+      std::map<const model::Sequence*, TimelineWidget*>::iterator
+        iterator = old_pages.find(sequence.get());
       if(iterator != old_pages.end())
         {
           // This sequence has not been changed
@@ -238,14 +241,14 @@ TimelinePanel::update_notebook()
         {
           // This is a new sequence, add it in
           TimelineWidget * const widget = new TimelineWidget(sequence);
-          notebook_pages[sequence] = widget;
+          notebook_pages[sequence.get()] = widget;
           notebook.append_page(*widget, sequence->get_name());
           notebook.set_tab_reorderable(*widget);
         }
     }
     
   // Free widgets which have been removed
-  pair<model::Sequence*, TimelineWidget*> pair; 
+  pair<const  model::Sequence*, TimelineWidget*> pair; 
   BOOST_FOREACH( pair, old_pages )
     delete pair.second;
     
diff --git a/src/gui/panels/timeline-panel.hpp b/src/gui/panels/timeline-panel.hpp
index d801ce08b..1966e711e 100644
--- a/src/gui/panels/timeline-panel.hpp
+++ b/src/gui/panels/timeline-panel.hpp
@@ -106,7 +106,8 @@ private:
   
   // Body Widgets
   Gtk::Notebook notebook;
-  std::map<model::Sequence*, TimelineWidget*> notebook_pages;
+  std::map< const model::Sequence*, TimelineWidget*>
+    notebook_pages;
   
   // Toolbar Widgets
   
diff --git a/src/gui/widgets/timeline-widget.cpp b/src/gui/widgets/timeline-widget.cpp
index 07fd3d6f9..f712b915d 100644
--- a/src/gui/widgets/timeline-widget.cpp
+++ b/src/gui/widgets/timeline-widget.cpp
@@ -37,7 +37,8 @@ const int TimelineWidget::HeaderWidth = 150;
 const double TimelineWidget::ZoomIncrement = 1.25;
 const int64_t TimelineWidget::MaxScale = 30000000;
 
-TimelineWidget::TimelineWidget(model::Sequence* const source_sequence) :
+TimelineWidget::TimelineWidget(
+  boost::shared_ptr<model::Sequence> source_sequence) :
   Table(2, 2),
   sequence(source_sequence),
   viewWindow(this, 0, 1),
@@ -53,7 +54,7 @@ TimelineWidget::TimelineWidget(model::Sequence* const source_sequence) :
   horizontalScroll(horizontalAdjustment),
   verticalScroll(verticalAdjustment)
 {
-  REQUIRE(sequence != NULL);
+  REQUIRE(sequence);
   
   body = new TimelineBody(this);
   ENSURE(body != NULL);
@@ -276,7 +277,7 @@ TimelineWidget::on_view_window_changed()
 void
 TimelineWidget::update_tracks()
 { 
-  REQUIRE(sequence != NULL);
+  REQUIRE(sequence);
   
   // Create timeline tracks from all the model tracks
   create_timeline_tracks();
@@ -297,7 +298,7 @@ TimelineWidget::update_tracks()
 void
 TimelineWidget::create_timeline_tracks()
 {
-  REQUIRE(sequence != NULL);
+  REQUIRE(sequence);
   
   BOOST_FOREACH(model::Track* child, sequence->get_tracks())
     create_timeline_tracks_from_branch(child);
@@ -345,7 +346,7 @@ TimelineWidget::create_timeline_track_from_model_track(
 timeline::Track*
 TimelineWidget::lookup_timeline_track(model::Track *model_track)
 {
-  ASSERT(sequence != NULL);  
+  REQUIRE(sequence);  
   std::map<model::Track*, timeline::Track*>::const_iterator iterator =
     trackMap.find(model_track);
   if(iterator == trackMap.end())
diff --git a/src/gui/widgets/timeline-widget.hpp b/src/gui/widgets/timeline-widget.hpp
index eb70aa45e..6e1c31c84 100644
--- a/src/gui/widgets/timeline-widget.hpp
+++ b/src/gui/widgets/timeline-widget.hpp
@@ -57,7 +57,7 @@ public:
   /**
    * Constructor
    */
-  TimelineWidget(model::Sequence *source_sequence);
+  TimelineWidget(boost::shared_ptr<model::Sequence> source_sequence);
 
   /**
    * Destructor
@@ -211,7 +211,7 @@ private:
 protected:
 
   // Model Data
-  model::Sequence* const sequence;
+  const boost::shared_ptr<model::Sequence> sequence;
   std::map<model::Track*, timeline::Track*> trackMap;
 
   // View State
diff --git a/src/gui/widgets/timeline/timeline-body.cpp b/src/gui/widgets/timeline/timeline-body.cpp
index 6456acce4..1601ba601 100644
--- a/src/gui/widgets/timeline/timeline-body.cpp
+++ b/src/gui/widgets/timeline/timeline-body.cpp
@@ -268,7 +268,7 @@ TimelineBody::draw_tracks(Cairo::RefPtr<Cairo::Context> cr)
 {
   REQUIRE(cr);
   REQUIRE(timelineWidget != NULL);
-  REQUIRE(timelineWidget->sequence != NULL);
+  REQUIRE(timelineWidget->sequence);
   
   // Prepare
   const Allocation allocation = get_allocation();
@@ -424,7 +424,7 @@ timeline::Track*
 TimelineBody::track_from_point(const int y) const
 {
   REQUIRE(timelineWidget != NULL);
-  REQUIRE(timelineWidget->sequence != NULL);
+  REQUIRE(timelineWidget->sequence);
   
   int offset = -get_vertical_offset();
   
diff --git a/src/gui/widgets/timeline/timeline-header-container.cpp b/src/gui/widgets/timeline/timeline-header-container.cpp
index 805807807..5bace4b4a 100644
--- a/src/gui/widgets/timeline/timeline-header-container.cpp
+++ b/src/gui/widgets/timeline/timeline-header-container.cpp
@@ -492,7 +492,7 @@ const std::list<model::Track*>&
 TimelineHeaderContainer::get_tracks() const
 {
   REQUIRE(timelineWidget != NULL);
-  REQUIRE(timelineWidget->sequence != NULL);
+  REQUIRE(timelineWidget->sequence);
   return timelineWidget->sequence->get_tracks();
 }