diff --git a/libs/ardour/ardour/triggerbox.h b/libs/ardour/ardour/triggerbox.h
index 23f7cacb4d..c565d9e3b1 100644
--- a/libs/ardour/ardour/triggerbox.h
+++ b/libs/ardour/ardour/triggerbox.h
@@ -167,6 +167,9 @@ class LIBARDOUR_API Trigger : public PBD::Stateful {
 	virtual void jump_start ();
 	virtual void jump_stop ();
 
+	void set_ui (void*);
+	void* ui () const { return _ui; }
+
   protected:
 	TriggerBox& _box;
 	State _state;
@@ -182,6 +185,7 @@ class LIBARDOUR_API Trigger : public PBD::Stateful {
 	Temporal::BBT_Offset _quantization;
 	bool _legato;
 	std::string _name;
+	void* _ui;
 
 	void set_region_internal (boost::shared_ptr<Region>);
 	void request_state (State s);
diff --git a/libs/ardour/triggerbox.cc b/libs/ardour/triggerbox.cc
index 3f50900405..6116e47445 100644
--- a/libs/ardour/triggerbox.cc
+++ b/libs/ardour/triggerbox.cc
@@ -48,6 +48,7 @@ Trigger::Trigger (size_t n, TriggerBox& b)
 	, _follow_action_probability (100)
 	, _quantization (Temporal::BBT_Offset (0, 1, 0))
 	, _legato (true)
+	, _ui (0)
 {
 }
 
@@ -57,6 +58,12 @@ Trigger::set_name (std::string const & str)
 	_name = str;
 }
 
+void
+Trigger::set_ui (void* p)
+{
+	_ui = p;
+}
+
 void
 Trigger::bang ()
 {