diff --git a/include/osgViewer/Viewer b/include/osgViewer/Viewer
index 556f53caf..895392fed 100644
--- a/include/osgViewer/Viewer
+++ b/include/osgViewer/Viewer
@@ -66,7 +66,7 @@ class OSGVIEWER_EXPORT Viewer : public osgViewer::View
           * Also calls realize() if the viewer is not already realized,
           * and installs trackball manipulator if one is not already assigned.
           */
-        virtual void run();
+        virtual int run();
 
         /** Render a complete new frame.
           * Calls frameAdvance(), frameEventTraversal(), frameUpateTraversal(), frameRenderingTraversals(). */
diff --git a/src/osgViewer/Viewer.cpp b/src/osgViewer/Viewer.cpp
index 4ba9cd793..d530c6f44 100644
--- a/src/osgViewer/Viewer.cpp
+++ b/src/osgViewer/Viewer.cpp
@@ -66,13 +66,13 @@ bool Viewer::isRealized() const
     return numRealizedWindows > 0;
 }
 
-void Viewer::run()
+int Viewer::run()
 {
     // if we don't have any scene graph assigned then just return
     if (!getSceneData())
     {
         osg::notify(osg::NOTICE)<<"Warning: Viewer::run() called without a scene graph being assigned to the viewer, cannot run."<<std::endl;
-        return;
+        return 1;
     }
 
     if (!getCameraManipulator())
@@ -89,6 +89,8 @@ void Viewer::run()
     {
         frame();
     }
+    
+    return 0;
 }
 
 void Viewer::setThreadingModel(ThreadingModel threadingModel)