diff --git a/src/Command/WebHook/HandleWebHook/EventDispatcherInterface.php b/src/Command/WebHook/HandleWebHook/EventDispatcherInterface.php
new file mode 100644
index 0000000..8e478b1
--- /dev/null
+++ b/src/Command/WebHook/HandleWebHook/EventDispatcherInterface.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace Sokil\Viber\Notifier\Command\WebHook\HandleWebHook;
+
+interface EventDispatcherInterface
+{
+    /**
+     * @param $eventName
+     * @param array $payload
+     *
+     * @return void
+     */
+    public function dispatch($eventName, array $payload);
+
+    /**
+     * @param $eventName
+     * @param $callable
+     *
+     * @return void
+     */
+    public function addListener($eventName, $callable);
+}
\ No newline at end of file
diff --git a/src/Command/WebHook/HandleWebHook/HandleWebHookCommandHandler.php b/src/Command/WebHook/HandleWebHook/HandleWebHookCommandHandler.php
index 35ec0c4..a3a2cd1 100644
--- a/src/Command/WebHook/HandleWebHook/HandleWebHookCommandHandler.php
+++ b/src/Command/WebHook/HandleWebHook/HandleWebHookCommandHandler.php
@@ -6,6 +6,9 @@
 use Sokil\Viber\Notifier\Repository\SubscribersRepositoryInterface;
 use Sokil\Viber\Notifier\Command\CommandHandlerInterface;
 
+/**
+ * @link https://developers.viber.com/docs/api/rest-bot-api/#callbacks
+ */
 class HandleWebHookCommandHandler implements CommandHandlerInterface
 {
     /**
@@ -13,12 +16,20 @@ class HandleWebHookCommandHandler implements CommandHandlerInterface
      */
     private $subscriberRepository;
 
+    /**
+     * @var EventDispatcherInterface
+     */
+    private $eventDispatcher;
+
     /**
      * @param SubscribersRepositoryInterface $subscriberRepository
      */
-    public function __construct(SubscribersRepositoryInterface $subscriberRepository)
-    {
+    public function __construct(
+        SubscribersRepositoryInterface $subscriberRepository,
+        EventDispatcherInterface $eventDispatcher = null
+    ) {
         $this->subscriberRepository = $subscriberRepository;
+        $this->eventDispatcher = $eventDispatcher;
     }
 
     /**
@@ -35,11 +46,16 @@ public function handle($command)
             );
         }
 
-        $request = $command->getWebHookServerRequestBody();
-        $event = !empty($request['event']) ? $request['event'] : null;
+        $webHookServerRequestBody = $command->getWebHookServerRequestBody();
+        $eventName = !empty($webHookServerRequestBody['event']) ? $webHookServerRequestBody['event'] : null;
+
+        // dispatch event
+        if ($this->eventDispatcher) {
+            $this->eventDispatcher->dispatch($eventName, $webHookServerRequestBody);
+        }
 
         // route
-        switch ($event) {
+        switch ($eventName) {
             case 'webhook':
             case 'seen':
             case 'action':
@@ -50,23 +66,23 @@ public function handle($command)
 
             case 'subscribed':
             case 'conversation_started':
-                if (isset($request['user']['id'])) {
+                if (isset($webHookServerRequestBody['user']['id'])) {
                     $this->subscriberRepository->subscribe(
-                        new SubscriberId($request['user']['id']),
-                        $request['user']['name']
+                        new SubscriberId($webHookServerRequestBody['user']['id']),
+                        $webHookServerRequestBody['user']['name']
                     );
                 }
 
                 break;
 
             case 'unsubscribed':
-                if (isset($request['user_id'])) {
-                    $this->subscriberRepository->unsubscribe(new SubscriberId($request['user_id']));
+                if (isset($webHookServerRequestBody['user_id'])) {
+                    $this->subscriberRepository->unsubscribe(new SubscriberId($webHookServerRequestBody['user_id']));
                 }
                 break;
 
             default:
-                throw new \InvalidArgumentException(sprintf('Unsupported event "%s"', $event));
+                throw new \InvalidArgumentException(sprintf('Unsupported event "%s"', $eventName));
         }
     }
 }
diff --git a/src/Message/RichMediaMessage/RichMediaMessage.php b/src/Message/RichMediaMessage/RichMediaMessage.php
index a601c5c..0e529fa 100644
--- a/src/Message/RichMediaMessage/RichMediaMessage.php
+++ b/src/Message/RichMediaMessage/RichMediaMessage.php
@@ -33,7 +33,7 @@ public function __construct(array $buttons)
     {
         $this->buttons = $buttons;
     }
-    
+
     function getMinimalApiVersion()
     {
         return 2;
diff --git a/src/Service/ViberClient/ViberClient.php b/src/Service/ViberClient/ViberClient.php
index daf3b84..f0dbd42 100644
--- a/src/Service/ViberClient/ViberClient.php
+++ b/src/Service/ViberClient/ViberClient.php
@@ -41,27 +41,28 @@ public function __construct(HttpClientInterface $httpClient, $authToken)
 
     /**
      * @param string $url
-     *
+     * @param array $eventTypes = null If null, subscribe to all events. Possible values (message, delivered, seen, failed, subscribed, unsubscribed, conversation_started)
      * @throws ViberApiRequestError
      */
-    public function setWebHookUrl($url)
+    public function setWebHookUrl($url, array $eventTypes = null)
     {
         try {
+            $query = [
+                "url" => (string)$url,
+                "send_name" => true,
+                "send_photo" => true,
+            ];
+
+            if (is_array($eventTypes)) {
+                $query['event_types'] = $eventTypes;
+            }
+
             $response = $this->httpClient->request(
                 self::BASE_URI . '/pa/set_webhook',
                 [
                     'X-Viber-Auth-Token' => $this->authToken,
                 ],
-                [
-                    "url" => (string)$url,
-                    "event_types" => [
-                        "subscribed",
-                        "unsubscribed",
-                        "conversation_started",
-                    ],
-                    "send_name" => true,
-                    "send_photo" => true,
-                ]
+                $query
             );
         } catch (\Exception $e) {
             throw new ViberApiRequestError(
diff --git a/src/Service/ViberClient/ViberClientInterface.php b/src/Service/ViberClient/ViberClientInterface.php
index 7f0bf10..bf2c849 100644
--- a/src/Service/ViberClient/ViberClientInterface.php
+++ b/src/Service/ViberClient/ViberClientInterface.php
@@ -20,10 +20,11 @@ interface ViberClientInterface
 {
     /**
      * @param string $url
+     * @param array|null $eventTypes If null, subscribe to all events. Possible values (message, delivered, seen, failed, subscribed, unsubscribed, conversation_started)
      *
      * @throws ViberApiRequestError
      */
-    public function setWebHookUrl($url);
+    public function setWebHookUrl($url, array $eventTypes = null);
 
     /**
      * @param string $senderName