diff --git a/libs/ardour/ardour/vst3_plugin.h b/libs/ardour/ardour/vst3_plugin.h
index 584cd23ae4..9fd87f250d 100644
--- a/libs/ardour/ardour/vst3_plugin.h
+++ b/libs/ardour/ardour/vst3_plugin.h
@@ -214,10 +214,6 @@ private:
 
 	void foward_signal (Presonus::IContextInfoHandler2*, FIDString) const;
 
-	PBD::ScopedConnectionList   _strip_connections;
-	PBD::ScopedConnectionList   _ac_connection_list;
-	std::set<Evoral::Parameter> _ac_subscriptions;
-
 	boost::shared_ptr<ARDOUR::VST3PluginModule> _module;
 
 	std::vector <Vst::IConnectionPoint*> _connections;
@@ -270,9 +266,14 @@ private:
 	std::vector<bool> _enabled_audio_in;
 	std::vector<bool> _enabled_audio_out;
 
-	boost::optional<uint32_t> _plugin_latency;
+	/* PSL extensions, control protocol */
+	ARDOUR::SessionObject*      _owner;
+	PBD::ScopedConnectionList   _strip_connections;
+	PBD::ScopedConnectionList   _ac_connection_list;
+	std::set<Evoral::Parameter> _ac_subscriptions;
+	bool                        _add_to_selection;
 
-	ARDOUR::SessionObject* _owner;
+	boost::optional<uint32_t> _plugin_latency;
 
 	int _n_inputs;
 	int _n_outputs;
diff --git a/libs/ardour/vst3_plugin.cc b/libs/ardour/vst3_plugin.cc
index 7afc3de7e3..ecacf609e6 100644
--- a/libs/ardour/vst3_plugin.cc
+++ b/libs/ardour/vst3_plugin.cc
@@ -43,6 +43,8 @@
 #include "ardour/vst3_module.h"
 #include "ardour/vst3_plugin.h"
 
+#include "control_protocol/control_protocol.h"
+
 #include "pbd/i18n.h"
 
 using namespace PBD;
@@ -974,6 +976,7 @@ VST3PI::VST3PI (boost::shared_ptr<ARDOUR::VST3PluginModule> m, std::string uniqu
 	, _block_size (0)
 	, _port_id_bypass (UINT32_MAX)
 	, _owner (0)
+	, _add_to_selection (false)
 	, _n_factory_presets (0)
 {
 	using namespace std;
@@ -2520,8 +2523,8 @@ VST3PI::getContextInfoValue (int32& value, FIDString id)
 	} else if (0 == strcmp (id, ContextInfo::kSelected)) {
 		value = s->is_selected () ? 1 : 0;
 	} else if (0 == strcmp (id, ContextInfo::kFocused)) {
-		value = s->is_selected () ? 1 : 0; // XXX
-		//consider ControlProtocol::first_selected_stripable () == s;
+		boost::shared_ptr<Stripable> stripable = ControlProtocol::first_selected_stripable ();
+		value = stripable && stripable.get () == s ? 1 : 0;
 	} else if (0 == strcmp (id, ContextInfo::kSendCount)) {
 		value = 0;
 		while (s->send_enable_controllable (value)) {
@@ -2675,10 +2678,17 @@ VST3PI::setContextInfoValue (FIDString id, int32 value)
 #endif
 		s->presentation_info ().set_color(value);
 	} else if (0 == strcmp (id, ContextInfo::kSelected)) {
-		DEBUG_TRACE (DEBUG::VST3Callbacks, string_compose ("VST3PI::setContextInfoValue<int>: NOT IMPLEMENTED (%1)\n", id));
-		return kNotImplemented;
+		boost::shared_ptr<Stripable> stripable = s->session().stripable_by_id (s->id ());
+		assert (stripable);
+		if (value == 0) {
+			ControlProtocol::RemoveStripableFromSelection (stripable);
+		} else if (_add_to_selection) {
+			ControlProtocol::AddStripableToSelection (stripable);
+		} else {
+			ControlProtocol::SetStripableSelection (stripable);
+		}
 	} else if (0 == strcmp (id, ContextInfo::kMultiSelect)) {
-		//_add_to_selection = value != 0;
+		_add_to_selection = value != 0;
 	} else if (0 == strcmp (id, ContextInfo::kMute)) {
 		boost::shared_ptr<AutomationControl> ac = lookup_ac (_owner, id);
 		if (ac) {