diff --git a/libs/ardour/ardour/source.h b/libs/ardour/ardour/source.h
index 919ac10913..224a259b8f 100644
--- a/libs/ardour/ardour/source.h
+++ b/libs/ardour/ardour/source.h
@@ -113,6 +113,9 @@ public:
 	void set_captured_xruns (XrunPositions const& xruns) { _xruns = xruns; }
 
 	CueMarkers const & cue_markers() const { return _cue_markers; }
+	void add_cue_marker (CueMarker const &);
+	void remove_cue_marker (CueMarker const &);
+	PBD::Signal0<void> CueMarkersChanged;
 
 	virtual samplepos_t natural_position() const { return _natural_position; }
 	virtual void set_natural_position (samplepos_t pos);
diff --git a/libs/ardour/source.cc b/libs/ardour/source.cc
index 1fd8595b70..f8f43d60e5 100644
--- a/libs/ardour/source.cc
+++ b/libs/ardour/source.cc
@@ -380,3 +380,19 @@ Source::writable () const
 {
         return (_flags & Writable) && _session.writable();
 }
+
+void
+Source::add_cue_marker (CueMarker const & cm)
+{
+	_cue_markers.insert (cm);
+	CueMarkersChanged(); /* EMIT SIGNAL */
+}
+
+void
+Source::remove_cue_marker (CueMarker const & cm)
+{
+	if (_cue_markers.erase (cm)) {
+		CueMarkersChanged(); /* EMIT SIGNAL */
+	}
+}
+