diff --git a/include/osgViewer/CompositeViewer b/include/osgViewer/CompositeViewer
index f5ca58f76..b1f7a5482 100644
--- a/include/osgViewer/CompositeViewer
+++ b/include/osgViewer/CompositeViewer
@@ -138,11 +138,21 @@ class OSGVIEWER_EXPORT CompositeViewer : public osg::Referenced
         typedef std::vector<osgViewer::Scene*> Scenes;
         void getScenes(Scenes& scenes, bool onlyValid=true);
 
-        void stopThreading();
-        void startThreading();        
-        void setUpRenderingSupport();
 
-    public:
+        /** Set the graphics operation to call on realization of the viewers graphics windows.*/
+        void setRealizeOperation(osg::GraphicsOperation* op) { _realizeOperation = op; }
+
+        /** Get the graphics operation to call on realization of the viewers graphics windows.*/
+        osg::GraphicsOperation* getRealizeOperation() { return _realizeOperation.get(); }
+
+        /** Stop any threads begin run by viewer.*/
+        void stopThreading();
+
+        /** Start any threads required by the viewer, as per viewers ThreadingModel.*/
+        void startThreading();        
+
+        /** Set up the GraphicsOperations to render the various viewer cameras on the viewers graphics windows.*/
+        void setUpRenderingSupport();
 
 
     protected:
@@ -180,6 +190,8 @@ class OSGVIEWER_EXPORT CompositeViewer : public osg::Referenced
         
         osg::ref_ptr<osgGA::EventQueue>     _eventQueue;
         osg::ref_ptr<osgGA::EventVisitor>   _eventVisitor;
+
+        osg::ref_ptr<osg::GraphicsOperation> _realizeOperation;
 };
 
 
diff --git a/include/osgViewer/Viewer b/include/osgViewer/Viewer
index cce614c4d..64e22c5f9 100644
--- a/include/osgViewer/Viewer
+++ b/include/osgViewer/Viewer
@@ -123,8 +123,19 @@ class OSGVIEWER_EXPORT Viewer : public osgViewer::View
         typedef std::vector<osgViewer::GraphicsWindow*> Windows;
         void getWindows(Windows& windows, bool onlyValid=true);
 
+        /** Set the graphics operation to call on realization of the viewers graphics windows.*/
+        void setRealizeOperation(osg::GraphicsOperation* op) { _realizeOperation = op; }
+
+        /** Get the graphics operation to call on realization of the viewers graphics windows.*/
+        osg::GraphicsOperation* getRealizeOperation() { return _realizeOperation.get(); }
+
+        /** Stop any threads begin run by viewer.*/
         void stopThreading();
+
+        /** Start any threads required by the viewer, as per viewers ThreadingModel.*/
         void startThreading();        
+
+        /** Set up the GraphicsOperations to render the various viewer cameras on the viewers graphics windows.*/
         void setUpRenderingSupport();
 
     protected:
@@ -156,6 +167,8 @@ class OSGVIEWER_EXPORT Viewer : public osgViewer::View
         osg::observer_ptr<osg::Camera>      _cameraWithFocus;
         
         osg::ref_ptr<osgGA::EventVisitor>   _eventVisitor;
+        
+        osg::ref_ptr<osg::GraphicsOperation> _realizeOperation;
 };
 
 
diff --git a/src/osgViewer/CompositeViewer.cpp b/src/osgViewer/CompositeViewer.cpp
index 9841c6f81..a119c64a4 100644
--- a/src/osgViewer/CompositeViewer.cpp
+++ b/src/osgViewer/CompositeViewer.cpp
@@ -694,7 +694,17 @@ void CompositeViewer::realize()
         citr != contexts.end();
         ++citr)
     {
-        (*citr)->realize();
+        osg::GraphicsContext* gc = *citr;
+        gc->realize();
+        
+        if (_realizeOperation.valid())
+        {
+            gc->makeCurrent();
+            
+            (*_realizeOperation)(gc);
+            
+            gc->releaseContext();
+        }
     }
     
     bool grabFocus = true;
diff --git a/src/osgViewer/Viewer.cpp b/src/osgViewer/Viewer.cpp
index 3b1e4e334..40ea37830 100644
--- a/src/osgViewer/Viewer.cpp
+++ b/src/osgViewer/Viewer.cpp
@@ -756,7 +756,17 @@ void Viewer::realize()
         citr != contexts.end();
         ++citr)
     {
-        (*citr)->realize();
+        osg::GraphicsContext* gc = *citr;
+        gc->realize();
+        
+        if (_realizeOperation.valid())
+        {
+            gc->makeCurrent();
+            
+            (*_realizeOperation)(gc);
+            
+            gc->releaseContext();
+        }
     }
     
     bool grabFocus = true;
@@ -774,14 +784,14 @@ void Viewer::realize()
         }
     }
     
-    
-    startThreading();
-
     // initialize the global timer to be relative to the current time.
     osg::Timer::instance()->setStartTick();
 
     // pass on the start tick to all the associated eventqueues
     setStartTick(osg::Timer::instance()->getStartTick());
+
+    startThreading();
+
 }