diff --git a/src/Symfony/Component/Workflow/EventListener/GuardListener.php b/src/Symfony/Component/Workflow/EventListener/GuardListener.php
index 20ba04c007..4d1065299d 100644
--- a/src/Symfony/Component/Workflow/EventListener/GuardListener.php
+++ b/src/Symfony/Component/Workflow/EventListener/GuardListener.php
@@ -16,6 +16,7 @@ use Symfony\Component\Security\Core\Authentication\Token\Storage\TokenStorageInt
 use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;
 use Symfony\Component\Security\Core\Role\RoleHierarchyInterface;
 use Symfony\Component\Workflow\Event\GuardEvent;
+use Symfony\Component\Workflow\Exception\InvalidTokenConfigurationException;
 
 /**
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
@@ -55,6 +56,10 @@ class GuardListener
     {
         $token = $this->tokenStorage->getToken();
 
+        if (null === $token) {
+            throw new InvalidTokenConfigurationException(sprintf('There are no tokens available for workflow %s.', $event->getWorkflowName()));
+        }
+
         if (null !== $this->roleHierarchy) {
             $roles = $this->roleHierarchy->getReachableRoles($token->getRoles());
         } else {
diff --git a/src/Symfony/Component/Workflow/Exception/InvalidTokenConfigurationException.php b/src/Symfony/Component/Workflow/Exception/InvalidTokenConfigurationException.php
new file mode 100644
index 0000000000..681d7a8bba
--- /dev/null
+++ b/src/Symfony/Component/Workflow/Exception/InvalidTokenConfigurationException.php
@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Workflow\Exception;
+
+/**
+ * Thrown by GuardListener when there is no token set, but guards are placed on a transition.
+ *
+ * @author Matt Johnson <matj1985@gmail.com>
+ */
+class InvalidTokenConfigurationException extends LogicException implements ExceptionInterface
+{
+}
diff --git a/src/Symfony/Component/Workflow/Tests/EventListener/GuardListenerTest.php b/src/Symfony/Component/Workflow/Tests/EventListener/GuardListenerTest.php
index b46ee9092c..741dcf0930 100644
--- a/src/Symfony/Component/Workflow/Tests/EventListener/GuardListenerTest.php
+++ b/src/Symfony/Component/Workflow/Tests/EventListener/GuardListenerTest.php
@@ -69,6 +69,18 @@ class GuardListenerTest extends TestCase
         $this->assertTrue($event->isBlocked());
     }
 
+    /**
+     * @expectedException \Symfony\Component\Workflow\Exception\InvalidTokenConfigurationException
+     * @expectedExceptionMessage There are no tokens available for workflow unnamed.
+     */
+    public function testWithNoTokensInTokenStorage()
+    {
+        $event = $this->createEvent();
+        $this->tokenStorage->setToken(null);
+
+        $this->listener->onTransition($event, 'event_name_a');
+    }
+
     private function createEvent()
     {
         $subject = new \stdClass();