diff --git a/dist/main.js b/dist/main.js
index 77dd7e8..edaad59 100644
--- a/dist/main.js
+++ b/dist/main.js
@@ -5,13 +5,13 @@ const mqtt = require("./mqttclient");
 class Dispatcher {
     constructor() {
         this._mqttClient = new mqtt.MqttClient();
-        this._mqttClient.register('IoT/test', (message) => {
+        this._mqttClient.register('IoT/test', 'print', (message) => {
             log.info("Callback for IoT/test");
             log.info(`message is ${message}`);
             return `<<${message}>>`;
         });
-        this._mqttClient.register('IoT/Device/#', mqtt.passThrough);
-        this._mqttClient.register('IoT/Device/#', mqtt.passThrough);
+        this._mqttClient.register('IoT/Device/#', 'null1', mqtt.passThrough);
+        this._mqttClient.register('IoT/Device/#', 'null2', mqtt.passThrough);
     }
     exec() {
         log.info("Dispatcher starting");
diff --git a/dist/mqttclient.js b/dist/mqttclient.js
index 1028fd1..6d3159b 100644
--- a/dist/mqttclient.js
+++ b/dist/mqttclient.js
@@ -3,6 +3,19 @@ Object.defineProperty(exports, "__esModule", { value: true });
 const Mqtt = require("mqtt");
 const log = require("./log");
 const MQTT_BROKER_DEFAULT_URL = "mqtt://localhost";
+class TopicHandlerCallback {
+    constructor(label, func) {
+        this._label = label;
+        this._func = func;
+    }
+    get func() {
+        return this._func;
+    }
+    toString() {
+        let funcName = (this._func.name === "") ? "lambda" : this._func.name;
+        return `<${funcName}, ${this._label}>`;
+    }
+}
 function passThrough(message) {
     return message;
 }
@@ -12,20 +25,19 @@ class MqttClient {
         this._mqttBrokerUrl = (mqttBrokerUrl) ? mqttBrokerUrl : MQTT_BROKER_DEFAULT_URL;
         this._topicHandlers = [];
     }
-    register(topic, callback) {
+    register(topic, label, callbackFunc) {
         let done = false;
-        let callbackName = (callback.name === "") ? "lambda" : callback.name;
+        let callback = new TopicHandlerCallback(label, callbackFunc);
         for (let topicHandler of this._topicHandlers) {
             if (topicHandler.topic === topic) {
                 topicHandler.callbacks.push(callback);
                 done = true;
-                log.info(`additional callback <${callbackName}> added for topic ${topic}`);
+                log.info(`additional callback ${callback.toString()} added for topic ${topic}`);
             }
         }
         if (!done) {
-            let cbs = [callback];
-            this._topicHandlers.push({ topic: topic, callbacks: cbs });
-            log.info(`first callback <${callbackName}> added for topic ${topic}`);
+            this._topicHandlers.push({ topic: topic, callbacks: [callback] });
+            log.info(`first callback ${callback.toString()} added for topic ${topic}`);
         }
     }
     exec() {
@@ -43,6 +55,12 @@ class MqttClient {
                 if (this.topicMatch(topicHandler.topic, topic)) {
                     log.info(`received topic ${topic} matches registered topic ${topicHandler.topic}`);
                     // topicHandler.callback(payload)
+                    let returnValue = payload;
+                    for (let topicHandlerCallback of topicHandler.callbacks) {
+                        log.info(`Calling ${topicHandlerCallback}`);
+                        returnValue = topicHandlerCallback.func(returnValue);
+                    }
+                    log.info(`Final return value is ${returnValue}`);
                 }
             }
         });
diff --git a/src/main.ts b/src/main.ts
index 6eb5a64..f8fdfab 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -7,13 +7,13 @@ class Dispatcher {
     constructor() {
         this._mqttClient = new mqtt.MqttClient()
 
-        this._mqttClient.register('IoT/test', (message: any) : any => {
+        this._mqttClient.register('IoT/test', 'print', (message: any) : any => {
             log.info("Callback for IoT/test")
             log.info(`message is ${message}`)
             return `<<${message}>>`
         })
-        this._mqttClient.register('IoT/Device/#', mqtt.passThrough)
-        this._mqttClient.register('IoT/Device/#', mqtt.passThrough)
+        this._mqttClient.register('IoT/Device/#', 'null1', mqtt.passThrough)
+        this._mqttClient.register('IoT/Device/#', 'null2', mqtt.passThrough)
     }
 
     exec() : void {
diff --git a/src/mqttclient.ts b/src/mqttclient.ts
index 148c78f..ca7602a 100644
--- a/src/mqttclient.ts
+++ b/src/mqttclient.ts
@@ -3,7 +3,23 @@ import * as log from './log'
 
 const MQTT_BROKER_DEFAULT_URL : string = "mqtt://localhost"
 
-type TopicHandlerCallback = (message: any) => any
+type TopicHandlerCallbackFunc = (message: any) => any
+
+class TopicHandlerCallback {
+    private _label: string
+    private _func: TopicHandlerCallbackFunc
+    constructor(label: string, func: TopicHandlerCallbackFunc) {
+        this._label = label
+        this._func = func
+    }
+    get func() : TopicHandlerCallbackFunc {
+        return this._func
+    }
+    public toString() : string {
+        let funcName : string = (this._func.name === "") ? "lambda" : this._func.name
+        return `<${funcName}, ${this._label}>`
+    }
+}
 
 interface TopicHandler {
     topic: string,
@@ -24,20 +40,19 @@ export class MqttClient {
         this._topicHandlers = []
     }
 
-    register(topic: string, callback: TopicHandlerCallback) : void {
+    register(topic: string, label: string, callbackFunc: TopicHandlerCallbackFunc) : void {
         let done: boolean = false
-        let callbackName : string = (callback.name === "") ? "lambda" : callback.name
+        let callback : TopicHandlerCallback = new TopicHandlerCallback(label, callbackFunc)
         for (let topicHandler of this._topicHandlers) {
             if (topicHandler.topic === topic) {
                 topicHandler.callbacks.push(callback)
                 done = true
-                log.info(`additional callback <${callbackName}> added for topic ${topic}`)
+                log.info(`additional callback ${callback.toString()} added for topic ${topic}`)
             }
         }
         if (! done) {
-            let cbs : TopicHandlerCallback[] = [ callback ]
-            this._topicHandlers.push({topic:topic, callbacks:cbs})
-            log.info(`first callback <${callbackName}> added for topic ${topic}`)
+            this._topicHandlers.push({topic: topic, callbacks:[ callback ]})
+            log.info(`first callback ${callback.toString()} added for topic ${topic}`)
         }
     }
 
@@ -56,6 +71,12 @@ export class MqttClient {
                 if (this.topicMatch(topicHandler.topic, topic)) {
                     log.info(`received topic ${topic} matches registered topic ${topicHandler.topic}`)
                     // topicHandler.callback(payload)
+                    let returnValue: any = payload
+                    for (let topicHandlerCallback of topicHandler.callbacks) {
+                        log.info(`Calling ${topicHandlerCallback}`)
+                        returnValue = topicHandlerCallback.func(returnValue)
+                    }
+                    log.info(`Final return value is ${returnValue}`)
                 }
             }
         })