diff --git a/src/gui/gtk-lumiera.hpp b/src/gui/gtk-lumiera.hpp
index 3a9b17159..fec25c9b3 100644
--- a/src/gui/gtk-lumiera.hpp
+++ b/src/gui/gtk-lumiera.hpp
@@ -39,6 +39,7 @@
 #include <boost/scoped_ptr.hpp>
 #include <boost/enable_shared_from_this.hpp>
 #include "lib/util.hpp"
+#include "lib/lumitime.hpp"
 
 #include "window-manager.hpp"
 
diff --git a/src/gui/widgets/timeline-widget.cpp b/src/gui/widgets/timeline-widget.cpp
index f4922c03e..721467536 100644
--- a/src/gui/widgets/timeline-widget.cpp
+++ b/src/gui/widgets/timeline-widget.cpp
@@ -30,6 +30,7 @@ using namespace std;
 using namespace boost;
 using namespace util;
 using namespace gui::widgets::timeline;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
@@ -157,7 +158,7 @@ TimelineWidget::get_hovering_track() const
 
 /* ===== Signals ===== */
 
-sigc::signal<void, gavl_time_t>
+sigc::signal<void, lumiera::Time>
 TimelineWidget::mouse_hover_signal() const
 {
   return mouseHoverSignal;
@@ -187,7 +188,7 @@ TimelineWidget::on_scroll()
 {
   if(state)
     state->get_view_window().set_time_offset(
-      horizontalAdjustment.get_value());
+      Time((gavl_time_t)horizontalAdjustment.get_value()));
 }
   
 void
diff --git a/src/gui/widgets/timeline-widget.hpp b/src/gui/widgets/timeline-widget.hpp
index 4ce4d9e72..41e368947 100644
--- a/src/gui/widgets/timeline-widget.hpp
+++ b/src/gui/widgets/timeline-widget.hpp
@@ -106,7 +106,7 @@ public:
   
 public:
   /* ===== Signals ===== */
-  sigc::signal<void, gavl_time_t> mouse_hover_signal() const;
+  sigc::signal<void, lumiera::Time> mouse_hover_signal() const;
   
   sigc::signal<void> playback_period_drag_released_signal() const;
   
@@ -264,7 +264,7 @@ protected:
   Gtk::VScrollbar verticalScroll;
   
   // Signals
-  sigc::signal<void, gavl_time_t> mouseHoverSignal;
+  sigc::signal<void, lumiera::Time> mouseHoverSignal;
   sigc::signal<void> playbackPeriodDragReleasedSignal;
   sigc::signal<void, boost::shared_ptr<timeline::Track> >
     hoveringTrackChangedSignal;
@@ -277,7 +277,7 @@ public:
   /**
    * The maximum scale for timeline display.
    * @remarks At MaxScale, every pixel on the timeline is equivalent
-   * to 30000000 gavl_time_t increments.
+   * to 30000000 lumiera::Time increments.
    */ 
   static const int64_t MaxScale;
   
diff --git a/src/gui/widgets/timeline/timeline-body.cpp b/src/gui/widgets/timeline/timeline-body.cpp
index b3077f00d..44eb9a472 100644
--- a/src/gui/widgets/timeline/timeline-body.cpp
+++ b/src/gui/widgets/timeline/timeline-body.cpp
@@ -34,6 +34,7 @@
 using namespace Gtk;
 using namespace std;
 using namespace boost;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
@@ -255,8 +256,8 @@ TimelineBody::on_motion_notify_event(GdkEventMotion *event)
             TimelineViewWindow &window = view_window();
             
             const int64_t scale = window.get_time_scale();
-            gavl_time_t offset = beginShiftTimeOffset +
-              (int64_t)(mouseDownX - event->x) * scale;
+            Time offset(beginShiftTimeOffset +
+              (int64_t)(mouseDownX - event->x) * scale);
             window.set_time_offset(offset);
             
             set_vertical_offset((int)(mouseDownY - event->y) +
diff --git a/src/gui/widgets/timeline/timeline-ibeam-tool.cpp b/src/gui/widgets/timeline/timeline-ibeam-tool.cpp
index 5aa9a3883..7e243ef7c 100644
--- a/src/gui/widgets/timeline/timeline-ibeam-tool.cpp
+++ b/src/gui/widgets/timeline/timeline-ibeam-tool.cpp
@@ -25,6 +25,7 @@
 
 using namespace boost;
 using namespace gui::widgets;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
@@ -95,7 +96,7 @@ IBeamTool::on_button_press_event(GdkEventButton* event)
   
   if(event->button == 1)
     {
-      const gavl_time_t time =
+      const Time time =
         state->get_view_window().x_to_time(event->x);
       
       if(is_mouse_in_start_drag_zone())
@@ -187,7 +188,7 @@ IBeamTool::set_leading_x(const int x)
   shared_ptr<TimelineState> state = get_state();
 
   const bool set_playback_period = dragType == Selection;
-  const gavl_time_t time = state->get_view_window().x_to_time(x);
+  const Time time = state->get_view_window().x_to_time(x);
   if(time > pinnedDragTime)
     state->set_selection(pinnedDragTime, time, set_playback_period);
   else
diff --git a/src/gui/widgets/timeline/timeline-ibeam-tool.hpp b/src/gui/widgets/timeline/timeline-ibeam-tool.hpp
index b1ee49378..5d05b14ba 100644
--- a/src/gui/widgets/timeline/timeline-ibeam-tool.hpp
+++ b/src/gui/widgets/timeline/timeline-ibeam-tool.hpp
@@ -164,7 +164,7 @@ private:
    * the mouse, the other is pinned. pinnedDragTime specifies the time
    * of that point.
    */
-  gavl_time_t pinnedDragTime;
+  lumiera::Time pinnedDragTime;
   
   /**
    * This connection is used to represent the timer which causes scroll
diff --git a/src/gui/widgets/timeline/timeline-ruler.cpp b/src/gui/widgets/timeline/timeline-ruler.cpp
index 23d3103ac..cce311007 100644
--- a/src/gui/widgets/timeline/timeline-ruler.cpp
+++ b/src/gui/widgets/timeline/timeline-ruler.cpp
@@ -37,6 +37,7 @@ using namespace boost;
 using namespace gui;
 using namespace gui::widgets;
 using namespace gui::widgets::timeline;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
@@ -235,7 +236,7 @@ TimelineRuler::set_leading_x(const int x)
   
   if(state)
     {
-      const gavl_time_t time = view_window().x_to_time(x);
+      const Time time = view_window().x_to_time(x);
       if(time > pinnedDragTime)
         state->set_playback_period(pinnedDragTime, time);
       else
diff --git a/src/gui/widgets/timeline/timeline-ruler.hpp b/src/gui/widgets/timeline/timeline-ruler.hpp
index 11f5be709..e47038ab1 100644
--- a/src/gui/widgets/timeline/timeline-ruler.hpp
+++ b/src/gui/widgets/timeline/timeline-ruler.hpp
@@ -198,7 +198,7 @@ private:
    * the mouse, the other is pinned. pinnedDragTime specifies the time
    * of that point.
    */
-  gavl_time_t pinnedDragTime;
+  lumiera::Time pinnedDragTime;
   
   // Indicated values
   /**
diff --git a/src/gui/widgets/timeline/timeline-state.cpp b/src/gui/widgets/timeline/timeline-state.cpp
index c15f095b5..e6a6e92c5 100644
--- a/src/gui/widgets/timeline/timeline-state.cpp
+++ b/src/gui/widgets/timeline/timeline-state.cpp
@@ -25,6 +25,7 @@
 using namespace boost;
 using namespace Gtk;
 using namespace sigc;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
@@ -33,17 +34,17 @@ namespace timeline {
 TimelineState::TimelineState(
   boost::shared_ptr<model::Sequence> source_sequence) :
   sequence(source_sequence),
-  viewWindow(0, 1),
+  viewWindow(Time(0), 1),
   selectionStart(0),
   selectionEnd(0),
   playbackPeriodStart(0),
   playbackPeriodEnd(0),
-  playbackPoint(GAVL_TIME_UNDEFINED)
+  playbackPoint(Time(GAVL_TIME_UNDEFINED))
 {
   REQUIRE(sequence);
   
   viewWindow.set_time_scale(GAVL_TIME_SCALE / 200);
-  set_selection(2000000, 4000000);
+  set_selection(Time(2000000), Time(4000000));
 }
 
 boost::shared_ptr<model::Sequence>
@@ -58,20 +59,20 @@ TimelineState::get_view_window()
   return viewWindow;
 }
 
-gavl_time_t
+Time
 TimelineState::get_selection_start() const
 {
   return selectionStart;
 }
 
-gavl_time_t
+Time
 TimelineState::get_selection_end() const
 {
   return selectionEnd;
 }
 
 void
-TimelineState::set_selection(gavl_time_t start, gavl_time_t end,
+TimelineState::set_selection(Time start, Time end,
   bool reset_playback_period)
 {    
   if(start < end)
@@ -95,20 +96,20 @@ TimelineState::set_selection(gavl_time_t start, gavl_time_t end,
   selectionChangedSignal.emit();
 }
 
-gavl_time_t
+Time
 TimelineState::get_playback_period_start() const
 {
   return playbackPeriodStart;
 }
   
-gavl_time_t
+Time
 TimelineState::get_playback_period_end() const
 {
   return playbackPeriodEnd;
 }
   
 void
-TimelineState::set_playback_period(gavl_time_t start, gavl_time_t end)
+TimelineState::set_playback_period(Time start, Time end)
 {
   
   if(start < end)
@@ -127,13 +128,13 @@ TimelineState::set_playback_period(gavl_time_t start, gavl_time_t end)
 }
 
 void
-TimelineState::set_playback_point(gavl_time_t point)
+TimelineState::set_playback_point(Time point)
 {
   playbackPoint = point;
   playbackChangedSignal.emit();
 }
 
-gavl_time_t
+Time
 TimelineState::get_playback_point() const
 {
   return playbackPoint;
diff --git a/src/gui/widgets/timeline/timeline-state.hpp b/src/gui/widgets/timeline/timeline-state.hpp
index 2c9c07043..431173240 100644
--- a/src/gui/widgets/timeline/timeline-state.hpp
+++ b/src/gui/widgets/timeline/timeline-state.hpp
@@ -70,12 +70,12 @@ public:
   /**
    * Gets the time at which the selection begins.
    */
-  gavl_time_t get_selection_start() const;
+  lumiera::Time get_selection_start() const;
   
   /**
    * Gets the time at which the selection begins.
    */
-  gavl_time_t get_selection_end() const;
+  lumiera::Time get_selection_end() const;
   
   /**
    * Sets the period of the selection.
@@ -84,39 +84,39 @@ public:
    * @param reset_playback_period Specifies whether to set the playback
    * period to the same as this new selection.
    */
-  void set_selection(gavl_time_t start, gavl_time_t end,
+  void set_selection(lumiera::Time start, lumiera::Time end,
     bool reset_playback_period = true);
   
   /**
    * Gets the time at which the playback period begins.
    */
-  gavl_time_t get_playback_period_start() const;
+  lumiera::Time get_playback_period_start() const;
   
   /**
    * Gets the time at which the playback period ends.
    */
-  gavl_time_t get_playback_period_end() const;
+  lumiera::Time get_playback_period_end() const;
   
   /**
    * Sets the playback period.
    * @param start The start time.
    * @param end The end time.
    */
-  void set_playback_period(gavl_time_t start, gavl_time_t end);
+  void set_playback_period(lumiera::Time start, lumiera::Time end);
   
   /**
    * Sets the time which is currenty being played back.
    * @param point The time index being played. This value may be
    * GAVL_TIME_UNDEFINED, if there is no playback point.
    */
-  void set_playback_point(gavl_time_t point);
+  void set_playback_point(lumiera::Time point);
   
   /**
    * Gets the current playback point.
    * @return The time index of the playback point. This value may be
    * GAVL_TIME_UNDEFINED, if there is no playback point.
    */
-  gavl_time_t get_playback_point() const;
+  lumiera::Time get_playback_point() const;
   
   /**
    * A signal to notify when the selected period has changed.
@@ -150,27 +150,27 @@ private:
   /**
    * The start time of the selection period.
    **/
-  gavl_time_t selectionStart;
+  lumiera::Time selectionStart;
   
   /**
    * The end time of the selection period.
    **/
-  gavl_time_t selectionEnd;
+  lumiera::Time selectionEnd;
   
   /**
    * The start time of the playback period.
    **/
-  gavl_time_t playbackPeriodStart;
+  lumiera::Time playbackPeriodStart;
   
   /**
    * The end time of the playback period.
    **/
-  gavl_time_t playbackPeriodEnd;
+  lumiera::Time playbackPeriodEnd;
   
   /**
    * The time of the playback point.
    **/
-  gavl_time_t playbackPoint;
+  lumiera::Time playbackPoint;
   
   // Signals
   
diff --git a/src/gui/widgets/timeline/timeline-view-window.cpp b/src/gui/widgets/timeline/timeline-view-window.cpp
index 3eb469b7e..e5283a24a 100644
--- a/src/gui/widgets/timeline/timeline-view-window.cpp
+++ b/src/gui/widgets/timeline/timeline-view-window.cpp
@@ -25,26 +25,27 @@
 
 using namespace Gtk;
 using namespace gui::widgets;
+using namespace lumiera;
 
 namespace gui {
 namespace widgets {
 namespace timeline {
 
 TimelineViewWindow::TimelineViewWindow(
-  gavl_time_t offset, int64_t scale) :
+  Time offset, int64_t scale) :
   timeOffset(offset),
   timeScale(scale)
 {
 }
 
-gavl_time_t
+Time
 TimelineViewWindow::get_time_offset() const
 {
   return timeOffset;
 }
 
 void
-TimelineViewWindow::set_time_offset(gavl_time_t offset)
+TimelineViewWindow::set_time_offset(Time offset)
 {
   timeOffset = offset;
   changedSignal.emit();
@@ -80,8 +81,8 @@ TimelineViewWindow::zoom_view(int point, int zoom_size)
     new_time_scale = TimelineWidget::MaxScale;
   
   // The view must be shifted so that the zoom is centred on the cursor
-  set_time_offset(get_time_offset() +
-    (timeScale - new_time_scale) * point);
+  set_time_offset(Time((gavl_time_t)get_time_offset() +
+    (timeScale - new_time_scale) * point));
     
   // Apply the new scale
   set_time_scale(new_time_scale);
@@ -90,8 +91,8 @@ TimelineViewWindow::zoom_view(int point, int zoom_size)
 void
 TimelineViewWindow::shift_view(int view_width, int shift_size)
 {
-  set_time_offset(get_time_offset() +
-    shift_size * timeScale * view_width / 256);
+  set_time_offset(Time((gavl_time_t)get_time_offset() +
+    shift_size * timeScale * view_width / 256));
 }
 
 int
@@ -100,10 +101,10 @@ TimelineViewWindow::time_to_x(gavl_time_t time) const
   return (int)((time - timeOffset) / timeScale);
 }
 
-gavl_time_t
+Time
 TimelineViewWindow::x_to_time(int x) const
 {
-  return (gavl_time_t)((int64_t)x * timeScale + timeOffset);
+  return Time((gavl_time_t)((int64_t)x * timeScale + timeOffset));
 }
 
 sigc::signal<void>
diff --git a/src/gui/widgets/timeline/timeline-view-window.hpp b/src/gui/widgets/timeline/timeline-view-window.hpp
index d1e1039ad..8689b6ce6 100644
--- a/src/gui/widgets/timeline/timeline-view-window.hpp
+++ b/src/gui/widgets/timeline/timeline-view-window.hpp
@@ -50,19 +50,19 @@ public:
    * @param offset The initial view offset.
    * @param scale The initial scale.
    **/
-  TimelineViewWindow(gavl_time_t offset, int64_t scale);
+  TimelineViewWindow(lumiera::Time offset, int64_t scale);
     
   /**
    * Gets the time offset. This is the time value displaid at the
    * left-hand edge of the timeline body area.
    */
-  gavl_time_t get_time_offset() const;
+  lumiera::Time get_time_offset() const;
 
   /**
    * Sets the time offset. This is the time value displaid at the
    * left-hand edge of the timeline body area.
    */
-  void set_time_offset(gavl_time_t time_offset);
+  void set_time_offset(lumiera::Time time_offset);
   
   /**
    * Gets the time scale value.
@@ -108,7 +108,7 @@ public:
    * the timeline body) to convert.
    * @return Returns the time at the coordinate.
    **/
-  gavl_time_t x_to_time(int x) const;
+  lumiera::Time x_to_time(int x) const;
   
   /**
    * A signal to indicate that the scale or offset have been changed.
@@ -116,7 +116,7 @@ public:
   sigc::signal<void> changed_signal() const; 
 
 private:
-  gavl_time_t timeOffset;
+  lumiera::Time timeOffset;
   int64_t timeScale;
   
   sigc::signal<void> changedSignal;