diff --git a/composer.json b/composer.json
index ff59374..6d7f0a2 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,8 @@
     },
     "require": {
         "php": ">=5.5",
-        "zendframework/zend-stdlib": "~2.5"
+        "zendframework/zend-stdlib": "~2.5",
+        "zendframework/zend-eventmanager": "^3.0.0"
     },
     "require-dev": {
         "zendframework/zend-db": "~2.5",
diff --git a/cookbook/2fa.php b/cookbook/2fa.php
new file mode 100644
index 0000000..33dfeba
--- /dev/null
+++ b/cookbook/2fa.php
@@ -0,0 +1,73 @@
+<?php
+
+/**
+ * I've left this in as a demonstration of a possible solution, however I think the complexities of 2fa should be
+ * considered separately - possibly even in it's own (zend-2fa) module.
+ */
+
+
+use Zend\Authentication\AuthenticationService;
+use Zend\EventManager\EventManager;
+
+class TwoFAListener
+{
+    public function onAuthenticate(\Zend\Authentication\Event\Authenticate $event)
+    {
+        $result = $event->getResult();
+        if ($result->isValid()) {
+            $prevResult = $event->getPreviousResult();
+            $identity = $result->getIdentity();
+
+            if ($prevResult !== null) {
+                $identity = $prevResult->getIdentity();
+            }
+
+            if (isset($identity['do2fa']) && $identity['do2fa']) {
+                $twoFactorResponse = $event->getParam('twoFactorResponse');
+
+                if (isset($twoFactorResponse)) {
+                    if (
+                        $prevResult !== null &&
+                        isset($prevResult->twoFactorToken) &&
+                        $twoFactorResponse === $prevResult->twoFactorToken
+                    ) {
+                        $result = new \Zend\Authentication\Result(\Zend\Authentication\Result::SUCCESS, $identity);
+                        $event->setResult($result);
+
+                        return $result;
+                    }
+                }
+
+                $result = new \Zend\Authentication\Result(-4, $identity, 'Requires 2 factor Auth');
+                $result->twoFactorToken = 'efg456'; //generate randomly
+                $event->setResult($result);
+                $event->stopPropagation();
+
+                return $result;
+
+            }
+        }
+
+        return $result;
+    }
+}
+
+$twoFaListener = new TwoFAListener();
+
+$callback = function ($identity, $credential) {
+    if ($identity === $credential) {
+        return new \Zend\Stdlib\ArrayObject(['identity' => $identity, 'credential' => $credential, 'do2fa' => true]);
+    }
+
+    throw new \Exception('Authentication failed');
+};
+
+$adapter = new \Zend\Authentication\Adapter\Callback($callback);
+
+$authService = new AuthenticationService(null, $adapter);
+$authService->addListener('Authenticate', [$TwoFAlistener, 'onAuthenticate'], 20);
+
+$authService->authenticate(['identity' => 'test', 'credential' => 'test']);
+
+//result success with test identity
+$authService->authenticate(['twoFactorResponse' => 'efg456']);
\ No newline at end of file
diff --git a/cookbook/AuditLog.php b/cookbook/AuditLog.php
new file mode 100644
index 0000000..da27ea9
--- /dev/null
+++ b/cookbook/AuditLog.php
@@ -0,0 +1,43 @@
+<?php
+
+use Zend\Authentication\AuthenticationService;
+use Zend\EventManager\EventManager;
+
+class AuditLog
+{
+    private $log;
+
+    /**
+     * AuditLog constructor.
+     * @TODO add dependency for a psr logger
+     * @param $log
+     */
+    public function __construct($log)
+    {
+        $this->log = $log;
+    }
+
+    public function onAuthenticationFailed(\Zend\Authentication\Event\Authenticate $event)
+    {
+        $this->log->warn(
+            sprintf('Authenication Failure for (%s) from (%s)', $event->getParam('identity'), $event->getParam('ip'))
+        );
+    }
+}
+
+$auditLog = new AuditLog(new stdClass());
+
+$callback = function ($identity, $credential) {
+    if ($identity === $credential) {
+        return new \Zend\Stdlib\ArrayObject(['identity' => $identity, 'credential' => $credential]);
+    }
+
+    throw new \Exception('Authentication failed');
+};
+
+$adapter = new \Zend\Authentication\Adapter\Callback($callback);
+
+$authService = new AuthenticationService(null, $adapter);
+$authService->addListener('AuthenticationFailed', [$auditLog, 'onAuthenticationFailed'] , -1);
+
+$authService->authenticate(['ip' => '127.0.0.1', 'identity' => 'test', 'credential' => 'failed']);
diff --git a/cookbook/BruteForceProtection.php b/cookbook/BruteForceProtection.php
new file mode 100644
index 0000000..b5da61c
--- /dev/null
+++ b/cookbook/BruteForceProtection.php
@@ -0,0 +1,79 @@
+<?php
+
+use Zend\Authentication\AuthenticationService;
+use Zend\EventManager\EventManager;
+
+class Firewall
+{
+    private $authFails = [];
+
+    public function getFailureCount($identifier)
+    {
+        if (isset($this->authFails[$identifier])) {
+            return $this->authFails[$identifier];
+        }
+
+        return 0;
+    }
+
+    public function onAuthenticate(\Zend\Authentication\Event\Authenticate $event)
+    {
+        $identity = $event->getParam('identity');
+        if ($identity !== null) {
+            if ($this->getFailurecount($identity) > 2) {
+                $result = new \Zend\Authentication\Result(-4, $identity, 'Too many failed attempts');
+                $event->setResult($result);
+                $event->stopPropagation();
+
+                return $result;
+            }
+        }
+
+        $ip = $event->getParam('ip');
+        if ($ip !== null) {
+            if ($this->getFailurecount($ip) > 2) {
+                $result = new \Zend\Authentication\Result(-4, $ip, 'Too many failed attempts');
+                $event->setResult($result);
+                $event->stopPropagation();
+
+                return $result;
+            }
+        }
+    }
+
+    public function onAuthenticationFailed(\Zend\Authentication\Event\Authenticate $event)
+    {
+        $identity = $event->getParam('identity');
+        if ($identity !== null) {
+            $this->authFails[$identity]++;
+        }
+
+        $ip = $event->getParam('ip');
+        if ($ip !== null) {
+            $this->authFails[$ip]++;
+        }
+    }
+}
+
+$firewall = new Firewall();
+
+$callback = function ($identity, $credential) {
+    if ($identity === $credential) {
+        return new \Zend\Stdlib\ArrayObject(['identity' => $identity, 'credential' => $credential]);
+    }
+
+    throw new \Exception('Authentication failed');
+};
+
+$adapter = new \Zend\Authentication\Adapter\Callback($callback);
+
+$authService = new AuthenticationService(null, $adapter, 10);
+$authService->addListener('Authenticate', [$firewall, 'onAuthenticate'] , -1);
+$authService->addListener('AuthenticationFailed', [$firewall, 'onAuthenticationFailed'] , -1);
+
+$authService->authenticate(['ip' => '127.0.0.1', 'identity' => 'test', 'credential' => 'failed']);
+$authService->authenticate(['ip' => '127.0.0.1', 'identity' => 'test', 'credential' => 'failed']);
+$authService->authenticate(['ip' => '127.0.0.1', 'identity' => 'test2', 'credential' => 'failed']);
+
+// result = failure to many attempts
+$authService->authenticate(['ip' => '127.0.0.1', 'identity' => 'test2', 'credential' => 'failed']);
\ No newline at end of file
diff --git a/cookbook/ChainedAuthentication.php b/cookbook/ChainedAuthentication.php
new file mode 100644
index 0000000..4252b27
--- /dev/null
+++ b/cookbook/ChainedAuthentication.php
@@ -0,0 +1,34 @@
+<?php
+
+use Zend\Authentication\AuthenticationService;
+use Zend\EventManager\EventManager;
+
+$callback = function ($identity, $credential) {
+    if ($identity === $credential) {
+        return new \Zend\Stdlib\ArrayObject(['identity' => $identity, 'credential' => $credential]);
+    }
+
+    throw new \Exception('Authentication failed');
+};
+
+$adapter = new \Zend\Authentication\Adapter\Callback($callback);
+
+$callback2 = function ($identity, $credential) {
+    if ($identity === 'test' && $credential === 'tester') {
+        return new \Zend\Stdlib\ArrayObject(['identity' => $identity, 'credential' => $credential]);
+    }
+
+    throw new \Exception('Authentication failed');
+};
+
+$adapter2 = new \Zend\Authentication\Adapter\Callback($callback2);
+
+$authService = new AuthenticationService(null, $adapter, 10);
+$authService->addAdapter($adapter2, 20);
+
+//auths against adapter 1
+$authService->authenticate(['identity' => 'test', 'credential' => 'test']);
+
+//auths against adapter 2
+$authService->authenticate(['identity' => 'test', 'credential' => 'tester']);
+
diff --git a/src/AuthenticationService.php b/src/AuthenticationService.php
index 06e82e2..acb8171 100644
--- a/src/AuthenticationService.php
+++ b/src/AuthenticationService.php
@@ -9,6 +9,13 @@
 
 namespace Zend\Authentication;
 
+use Zend\Authentication\Event\Authenticate;
+use Zend\Authentication\Event\AuthenticationFailed;
+use Zend\Authentication\Event\AuthenticationSucceeded;
+use Zend\Authentication\Listener\AuthenticationAdapterListener;
+use Zend\EventManager\EventManager;
+use Zend\EventManager\EventManagerInterface;
+
 class AuthenticationService implements AuthenticationServiceInterface
 {
     /**
@@ -21,49 +28,28 @@ class AuthenticationService implements AuthenticationServiceInterface
     /**
      * Authentication adapter
      *
-     * @var Adapter\AdapterInterface
+     * @var EventManagerInterface
      */
-    protected $adapter = null;
+    protected $events;
 
     /**
      * Constructor
      *
-     * @param  Storage\StorageInterface $storage
-     * @param  Adapter\AdapterInterface $adapter
+     * @param EventManagerInterface $eventManager
+     * @param Storage\StorageInterface $storage
      */
-    public function __construct(Storage\StorageInterface $storage = null, Adapter\AdapterInterface $adapter = null)
+    public function __construct(Storage\StorageInterface $storage = null, Adapter\AdapterInterface $adapter = null, $priority = 10)
     {
         if (null !== $storage) {
             $this->setStorage($storage);
         }
-        if (null !== $adapter) {
-            $this->setAdapter($adapter);
+
+        $this->events = new EventManager();
+        if ($adapter !== null) {
+            $this->addAdapter($adapter, $priority);
         }
     }
 
-    /**
-     * Returns the authentication adapter
-     *
-     * The adapter does not have a default if the storage adapter has not been set.
-     *
-     * @return Adapter\AdapterInterface|null
-     */
-    public function getAdapter()
-    {
-        return $this->adapter;
-    }
-
-    /**
-     * Sets the authentication adapter
-     *
-     * @param  Adapter\AdapterInterface $adapter
-     * @return AuthenticationService Provides a fluent interface
-     */
-    public function setAdapter(Adapter\AdapterInterface $adapter)
-    {
-        $this->adapter = $adapter;
-        return $this;
-    }
 
     /**
      * Returns the persistent storage handler
@@ -96,18 +82,33 @@ public function setStorage(Storage\StorageInterface $storage)
     /**
      * Authenticates against the supplied adapter
      *
-     * @param  Adapter\AdapterInterface $adapter
+     * @? This is currently a BC break the original takes an auth adapter as a parameter. This still conforms to the interface though.
+     *
+     * @param array $authenticationContext
      * @return Result
-     * @throws Exception\RuntimeException
      */
-    public function authenticate(Adapter\AdapterInterface $adapter = null)
+    public function authenticate($authenticationContext = [])
     {
-        if (!$adapter) {
-            if (!$adapter = $this->getAdapter()) {
-                throw new Exception\RuntimeException('An adapter must be set or passed prior to calling authenticate()');
-            }
+        $event = new Authenticate();
+        $event->setTarget($this);
+        $event->setParams($authenticationContext);
+        $event->setPreviousResult($this->getResult());
+
+        $this->events->triggerEvent($event);
+
+        $result = $event->getResult();
+
+        if ($result->isValid()) {
+            $event = new AuthenticationSucceeded();
+        } else {
+            $event = new AuthenticationFailed();
         }
-        $result = $adapter->authenticate();
+
+        $event->setTarget($this);
+        $event->setResult($result);
+        $event->setParams($authenticationContext);
+
+        $this->events->trigger($event);
 
         /**
          * ZF-7546 - prevent multiple successive calls from storing inconsistent results
@@ -117,9 +118,7 @@ public function authenticate(Adapter\AdapterInterface $adapter = null)
             $this->clearIdentity();
         }
 
-        if ($result->isValid()) {
-            $this->getStorage()->write($result->getIdentity());
-        }
+        $this->getStorage()->write($result);
 
         return $result;
     }
@@ -131,7 +130,7 @@ public function authenticate(Adapter\AdapterInterface $adapter = null)
      */
     public function hasIdentity()
     {
-        return !$this->getStorage()->isEmpty();
+        return !$this->getStorage()->isEmpty() && $this->getStorage()->read()->isValid();
     }
 
     /**
@@ -141,13 +140,13 @@ public function hasIdentity()
      */
     public function getIdentity()
     {
-        $storage = $this->getStorage();
+        $result = $this->getResult();
 
-        if ($storage->isEmpty()) {
-            return;
+        if ($result !== null && $result->isValid()) {
+            return $result->getIdentity();
         }
 
-        return $storage->read();
+        return null;
     }
 
     /**
@@ -159,4 +158,41 @@ public function clearIdentity()
     {
         $this->getStorage()->clear();
     }
+
+    /**
+     * @param Adapter\AdapterInterface $adapter
+     * @param int $priority
+     */
+    public function addAdapter(Adapter\AdapterInterface $adapter, $priority = 10)
+    {
+        $listener = new AuthenticationAdapterListener($adapter);
+        $this->events->attach('Authenticate', [$listener, 'onAuthenticate'], $priority);
+    }
+
+    /**
+     * @? Should there be a separate method for each event type instead of passing the event as a string?
+     *
+     * @param $event
+     * @param callable $listener
+     * @param $priority
+     */
+    public function addListener($event, callable $listener, $priority)
+    {
+        $this->events->attach($event, $listener, $priority);
+    }
+
+    /**
+     * @return Result|null
+     */
+    private function getResult()
+    {
+        $storage = $this->getStorage();
+
+        if ($storage->isEmpty()) {
+            return null;
+        }
+
+        $result = $storage->read();
+        return $result;
+    }
 }
diff --git a/src/Event/Authenticate.php b/src/Event/Authenticate.php
new file mode 100644
index 0000000..1eb8d9b
--- /dev/null
+++ b/src/Event/Authenticate.php
@@ -0,0 +1,46 @@
+<?php
+
+namespace Zend\Authentication\Event;
+
+use Zend\EventManager\Event;
+
+class Authenticate extends Event
+{
+    protected $name = 'Authenticate';
+
+    protected $result;
+
+    protected $previousResult;
+
+    /**
+     * @return mixed
+     */
+    public function getResult()
+    {
+        return $this->result;
+    }
+
+    /**
+     * @param mixed $result
+     */
+    public function setResult($result)
+    {
+        $this->result = $result;
+    }
+
+    /**
+     * @return mixed
+     */
+    public function getPreviousResult()
+    {
+        return $this->previousResult;
+    }
+
+    /**
+     * @param mixed $previousResult
+     */
+    public function setPreviousResult($previousResult)
+    {
+        $this->previousResult = $previousResult;
+    }
+}
\ No newline at end of file
diff --git a/src/Event/AuthenticationFailed.php b/src/Event/AuthenticationFailed.php
new file mode 100644
index 0000000..f2ab250
--- /dev/null
+++ b/src/Event/AuthenticationFailed.php
@@ -0,0 +1,28 @@
+<?php
+
+namespace Zend\Authentication\Event;
+
+use Zend\EventManager\Event;
+
+class AuthenticationFailed extends Event
+{
+    protected $name = 'AuthenticationFailed';
+
+    protected $result;
+
+    /**
+     * @return mixed
+     */
+    public function getResult()
+    {
+        return $this->result;
+    }
+
+    /**
+     * @param mixed $result
+     */
+    public function setResult($result)
+    {
+        $this->result = $result;
+    }
+}
\ No newline at end of file
diff --git a/src/Event/AuthenticationSucceeded.php b/src/Event/AuthenticationSucceeded.php
new file mode 100644
index 0000000..2095cdb
--- /dev/null
+++ b/src/Event/AuthenticationSucceeded.php
@@ -0,0 +1,28 @@
+<?php
+
+namespace Zend\Authentication\Event;
+
+use Zend\EventManager\Event;
+
+class AuthenticationSucceeded extends Event
+{
+    protected $name = 'AuthenticationSucceeded';
+
+    protected $result;
+
+    /**
+     * @return mixed
+     */
+    public function getResult()
+    {
+        return $this->result;
+    }
+
+    /**
+     * @param mixed $result
+     */
+    public function setResult($result)
+    {
+        $this->result = $result;
+    }
+}
\ No newline at end of file
diff --git a/src/Listener/AuthenticationAdapterListener.php b/src/Listener/AuthenticationAdapterListener.php
new file mode 100644
index 0000000..cc70df4
--- /dev/null
+++ b/src/Listener/AuthenticationAdapterListener.php
@@ -0,0 +1,45 @@
+<?php
+
+namespace Zend\Authentication\Listener;
+
+use Zend\Authentication\Adapter\AdapterInterface;
+use Zend\Authentication\Adapter\ValidatableAdapterInterface;
+use Zend\Authentication\Event\Authenticate;
+use Zend\Authentication\Result;
+
+class AuthenticationAdapterListener
+{
+    /**
+     * @var AdapterInterface
+     */
+    private $adapter;
+
+    /**
+     * AuthenticationAdapterListener constructor.
+     * @param AdapterInterface $adapter
+     */
+    public function __construct(AdapterInterface $adapter)
+    {
+        $this->adapter = $adapter;
+    }
+
+    public function onAuthenticate(Authenticate $event)
+    {
+        $result = $event->getResult();
+        if ($result instanceof Result && $result->isValid()) {
+            //If a previous adapter has already returned a valid result don't change that
+            return null;
+        }
+
+        if ($this->adapter instanceof ValidatableAdapterInterface) {
+            $this->adapter->setIdentity($event->getParam('identity'));
+            $this->adapter->setCredential($event->getParam('credential'));
+        }
+
+        $result = $this->adapter->authenticate();
+
+        $event->setResult($result);
+
+        return $result;
+    }
+}
\ No newline at end of file