diff --git a/audio/audio_config.go b/audio/audio_config.go
index 47f05ca..feffbf8 100644
--- a/audio/audio_config.go
+++ b/audio/audio_config.go
@@ -29,6 +29,7 @@ func (config AudioConfig) GetHandle() common.SPXHandle {
 // Close releases the underlying resources
 func (config AudioConfig) Close() {
 	config.properties.Close()
+	C.audio_config_release(config.handle)
 }
 
 func newAudioConfigFromHandle(handle C.SPXHANDLE) (*AudioConfig, error) {
diff --git a/dialog/callback_helpers.go b/dialog/callback_helpers.go
index 3524b49..f04657b 100644
--- a/dialog/callback_helpers.go
+++ b/dialog/callback_helpers.go
@@ -4,11 +4,14 @@
 package dialog
 
 import (
-	"github.com/Microsoft/cognitive-services-speech-sdk-go/speech"
 	"sync"
+
+	"github.com/Microsoft/cognitive-services-speech-sdk-go/speech"
 )
 
 // #include <speechapi_c_common.h>
+// #include <speechapi_c_recognizer.h>
+// #include <speechapi_c_dialog_service_connector.h>
 import "C"
 
 var mu sync.Mutex
@@ -29,11 +32,9 @@ func getSessionStartedCallback(handle C.SPXHANDLE) speech.SessionEventHandler {
 //export dialogFireEventSessionStarted
 func dialogFireEventSessionStarted(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSessionStartedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := speech.NewSessionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -56,11 +57,9 @@ func getSessionStoppedCallback(handle C.SPXHANDLE) speech.SessionEventHandler {
 //export dialogFireEventSessionStopped
 func dialogFireEventSessionStopped(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSessionStoppedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := speech.NewSessionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -83,11 +82,9 @@ func getRecognizedCallback(handle C.SPXHANDLE) speech.SpeechRecognitionEventHand
 //export dialogFireEventRecognized
 func dialogFireEventRecognized(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getRecognizedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := speech.NewSpeechRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -110,11 +107,9 @@ func getRecognizingCallback(handle C.SPXHANDLE) speech.SpeechRecognitionEventHan
 //export dialogFireEventRecognizing
 func dialogFireEventRecognizing(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getRecognizingCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := speech.NewSpeechRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -137,11 +132,9 @@ func getCanceledCallback(handle C.SPXHANDLE) speech.SpeechRecognitionCanceledEve
 //export dialogFireEventCanceled
 func dialogFireEventCanceled(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getCanceledCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := speech.NewSpeechRecognitionCanceledEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -164,11 +157,9 @@ func getActivityReceivedCallback(handle C.SPXHANDLE) ActivityReceivedEventHandle
 //export dialogFireEventActivityReceived
 func dialogFireEventActivityReceived(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getActivityReceivedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewActivityReceivedEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.dialog_service_connector_activity_received_event_release(handle)
 		return
 	}
 	handler(*event)
diff --git a/speech/callback_helpers.go b/speech/callback_helpers.go
index 7e93689..0c8a4cb 100644
--- a/speech/callback_helpers.go
+++ b/speech/callback_helpers.go
@@ -8,6 +8,8 @@ import (
 )
 
 // #include <speechapi_c_common.h>
+// #include <speechapi_c_recognizer.h>
+// #include <speechapi_c_synthesizer.h>
 import "C"
 
 var mu sync.Mutex
@@ -28,11 +30,9 @@ func getSessionStartedCallback(handle C.SPXHANDLE) SessionEventHandler {
 //export recognizerFireEventSessionStarted
 func recognizerFireEventSessionStarted(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSessionStartedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSessionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -55,11 +55,9 @@ func getSessionStoppedCallback(handle C.SPXHANDLE) SessionEventHandler {
 //export recognizerFireEventSessionStopped
 func recognizerFireEventSessionStopped(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSessionStoppedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSessionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -82,11 +80,9 @@ func getSpeechStartDetectedCallback(handle C.SPXHANDLE) RecognitionEventHandler
 //export recognizerFireEventSpeechStartDetected
 func recognizerFireEventSpeechStartDetected(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSpeechStartDetectedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -109,11 +105,9 @@ func getSpeechEndDetectedCallback(handle C.SPXHANDLE) RecognitionEventHandler {
 //export recognizerFireEventSpeechEndDetected
 func recognizerFireEventSpeechEndDetected(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSpeechEndDetectedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -136,11 +130,9 @@ func getRecognizedCallback(handle C.SPXHANDLE) SpeechRecognitionEventHandler {
 //export recognizerFireEventRecognized
 func recognizerFireEventRecognized(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getRecognizedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -163,11 +155,9 @@ func getRecognizingCallback(handle C.SPXHANDLE) SpeechRecognitionEventHandler {
 //export recognizerFireEventRecognizing
 func recognizerFireEventRecognizing(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getRecognizingCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechRecognitionEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -190,11 +180,9 @@ func getCanceledCallback(handle C.SPXHANDLE) SpeechRecognitionCanceledEventHandl
 //export recognizerFireEventCanceled
 func recognizerFireEventCanceled(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getCanceledCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechRecognitionCanceledEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.recognizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -217,11 +205,9 @@ func getSynthesisStartedCallback(handle C.SPXHANDLE) SpeechSynthesisEventHandler
 //export synthesizerFireEventSynthesisStarted
 func synthesizerFireEventSynthesisStarted(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisStartedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -244,11 +230,9 @@ func getSynthesizingCallback(handle C.SPXHANDLE) SpeechSynthesisEventHandler {
 //export synthesizerFireEventSynthesizing
 func synthesizerFireEventSynthesizing(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesizingCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -271,11 +255,9 @@ func getSynthesisCompletedCallback(handle C.SPXHANDLE) SpeechSynthesisEventHandl
 //export synthesizerFireEventSynthesisCompleted
 func synthesizerFireEventSynthesisCompleted(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisCompletedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -298,11 +280,9 @@ func getSynthesisCanceledCallback(handle C.SPXHANDLE) SpeechSynthesisEventHandle
 //export synthesizerFireEventSynthesisCanceled
 func synthesizerFireEventSynthesisCanceled(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisCanceledCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -325,11 +305,9 @@ func getSynthesisWordBoundaryCallback(handle C.SPXHANDLE) SpeechSynthesisWordBou
 //export synthesizerFireEventWordBoundary
 func synthesizerFireEventWordBoundary(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisWordBoundaryCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisWordBoundaryEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -352,11 +330,9 @@ func getSynthesisVisemeReceivedCallback(handle C.SPXHANDLE) SpeechSynthesisVisem
 //export synthesizerFireEventVisemeReceived
 func synthesizerFireEventVisemeReceived(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisVisemeReceivedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisVisemeEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
@@ -379,11 +355,9 @@ func getSynthesisBookmarkReachedCallback(handle C.SPXHANDLE) SpeechSynthesisBook
 //export synthesizerFireEventBookmarkReached
 func synthesizerFireEventBookmarkReached(handle C.SPXRECOHANDLE, eventHandle C.SPXEVENTHANDLE) {
 	handler := getSynthesisBookmarkReachedCallback(handle)
-	if handler == nil {
-		return
-	}
 	event, err := NewSpeechSynthesisBookmarkEventArgsFromHandle(handle2uintptr(eventHandle))
-	if err != nil {
+	if err != nil || handler == nil {
+		C.synthesizer_event_handle_release(handle)
 		return
 	}
 	handler(*event)
diff --git a/speech/session_event_args.go b/speech/session_event_args.go
index 44884a3..f7a0dc6 100644
--- a/speech/session_event_args.go
+++ b/speech/session_event_args.go
@@ -15,12 +15,14 @@ import "C"
 
 // SessionEventArgs represents the session event arguments.
 type SessionEventArgs struct {
+	handle C.SPXHANDLE
 	// SessionID Session identifier (a GUID in string format).
 	SessionID string
 }
 
 // Close releases the underlying resources.
 func (event SessionEventArgs) Close() {
+	C.recognizer_event_handle_release(event.handle)
 }
 
 // NewSessionEventArgsFromHandle creates the object from the handle (for internal use)
@@ -32,6 +34,7 @@ func NewSessionEventArgsFromHandle(handle common.SPXHandle) (*SessionEventArgs,
 		return nil, common.NewCarbonError(ret)
 	}
 	event := new(SessionEventArgs)
+	event.handle = uintptr2handle(handle)
 	event.SessionID = C.GoString((*C.char)(buffer))
 	return event, nil
 }
diff --git a/speech/speech_recognition_event_args.go b/speech/speech_recognition_event_args.go
index 45f51d5..fb5cc97 100644
--- a/speech/speech_recognition_event_args.go
+++ b/speech/speech_recognition_event_args.go
@@ -20,8 +20,8 @@ type SpeechRecognitionEventArgs struct {
 
 // Close releases the underlying resources
 func (event SpeechRecognitionEventArgs) Close() {
+	event.RecognitionEventArgs.Close()
 	event.Result.Close()
-	C.recognizer_event_handle_release(event.handle)
 }
 
 // NewSpeechRecognitionEventArgsFromHandle creates the object from the handle (for internal use)