diff --git a/src/Client.php b/src/Client.php
index 29ccfe7..7e1f381 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -12,6 +12,7 @@
 use UnexpectedValueException;
 use Clue\React\Ami\Protocol\Message;
 use Clue\React\Ami\Protocol\ErrorException;
+use Clue\React\Ami\Protocol\UnexpectedMessageException;
 
 class Client extends EventEmitter
 {
@@ -66,6 +67,7 @@ public function request(Action $message)
         return $deferred->promise();
     }
 
+    /** @internal */
     public function handleMessage(Message $message)
     {
         if ($message instanceof Event) {
@@ -74,8 +76,7 @@ public function handleMessage(Message $message)
         }
         $id = $message->getActionId();
         if (!isset($this->pending[$id])) {
-            var_dump('unexpected', $message);
-            // unexpected message
+            $this->emit('error', array(new UnexpectedMessageException($message), $this));
             return;
         }
 
diff --git a/src/Protocol/UnexpectedMessageException.php b/src/Protocol/UnexpectedMessageException.php
new file mode 100644
index 0000000..125ff74
--- /dev/null
+++ b/src/Protocol/UnexpectedMessageException.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace Clue\React\Ami\Protocol;
+
+use UnexpectedValueException;
+
+class UnexpectedMessageException extends UnexpectedValueException
+{
+    private $response;
+
+    public function __construct(Response $response)
+    {
+        parent::__construct('Unexpected message with action ID "' . $response->getActionId() . '" received');
+        $this->response = $response;
+    }
+
+    public function getResponse()
+    {
+        return $this->response;
+    }
+}
diff --git a/tests/ClientTest.php b/tests/ClientTest.php
index 2c523a2..c858c2e 100644
--- a/tests/ClientTest.php
+++ b/tests/ClientTest.php
@@ -4,6 +4,7 @@
 use Clue\React\Ami\Protocol\Parser;
 use Clue\React\Ami\Client;
 use React\EventLoop\Factory;
+use Clue\React\Ami\Protocol\Response;
 
 class ClientTest extends TestCase
 {
@@ -32,6 +33,16 @@ public function testParserExceptionForwardsErrorAndClosesClient()
         $stream->emit('data', array("invalid chunk\r\n\r\ninvalid chunk\r\n\r\n"));
     }
 
+    public function testUnexpectedResponseEmitsErrorAndClosesClient()
+    {
+        $client = new Client($this->createStreamMock());
+
+        $client->on('error', $this->expectCallableOnce());
+        $client->on('close', $this->expectCallableOnce());
+
+        $client->handleMessage(new Response(array('ActionID' => 1)));
+    }
+
     private function createStreamMock()
     {
         return new Stream(fopen('php://memory', 'r+'), $this->getMock('React\EventLoop\LoopInterface'));
diff --git a/tests/Protocol/UnexpectedMessageExceptionTest.php b/tests/Protocol/UnexpectedMessageExceptionTest.php
new file mode 100644
index 0000000..30a1a62
--- /dev/null
+++ b/tests/Protocol/UnexpectedMessageExceptionTest.php
@@ -0,0 +1,16 @@
+<?php
+
+use Clue\React\Ami\Protocol\Response;
+use Clue\React\Ami\Protocol\UnexpectedMessageException;
+
+class UnexpectedMessageExceptionTest extends TestCase
+{
+    public function testGetResponse()
+    {
+        $response = new Response(array('ActionID' => 1));
+
+        $exception = new UnexpectedMessageException($response);
+
+        $this->assertSame($response, $exception->getResponse());
+    }
+}