diff --git a/gtk2_ardour/marker_selection.h b/gtk2_ardour/marker_selection.h
index 6d4749f039..1b322d0885 100644
--- a/gtk2_ardour/marker_selection.h
+++ b/gtk2_ardour/marker_selection.h
@@ -24,9 +24,10 @@
 
 #include "marker.h"
 
-struct MarkerSelection : public std::list<ArdourMarker*>
+class MarkerSelection : public std::list<ArdourMarker*>
 {
-        void range (ARDOUR::framepos_t& start, ARDOUR::framepos_t& end);
+	public:
+		void range (ARDOUR::framepos_t& start, ARDOUR::framepos_t& end);
 };
 
 #endif /* __ardour_gtk_marker_selection_h__ */