diff --git a/src/Symfony/Component/DependencyInjection/Container.php b/src/Symfony/Component/DependencyInjection/Container.php
index 759bd45029835..cf29685c605f5 100644
--- a/src/Symfony/Component/DependencyInjection/Container.php
+++ b/src/Symfony/Component/DependencyInjection/Container.php
@@ -59,7 +59,7 @@
  *
  * @api
  */
-class Container implements ContainerInterface
+class Container implements IntrospectableContainerInterface
 {
     protected $parameterBag;
     protected $services;
@@ -265,6 +265,18 @@ public function get($id, $invalidBehavior = self::EXCEPTION_ON_INVALID_REFERENCE
             throw new ServiceNotFoundException($id);
         }
     }
+    
+    /**
+     * Returns true if the given service has actually been initialized
+     *
+     * @param string $id          The service identifier
+     *
+     * @return Boolean true if service has already been initialized, false otherwise
+     */
+    public function initialized($id)
+    {
+        return isset($this->services[strtolower($id)]);
+    }
 
     /**
      * Gets all service ids.
diff --git a/src/Symfony/Component/DependencyInjection/IntrospectableContainerInterface.php b/src/Symfony/Component/DependencyInjection/IntrospectableContainerInterface.php
new file mode 100644
index 0000000000000..726652c05e503
--- /dev/null
+++ b/src/Symfony/Component/DependencyInjection/IntrospectableContainerInterface.php
@@ -0,0 +1,33 @@
+<?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\DependencyInjection;
+
+/**
+ * IntrospectableContainerInterface defines additional introspection functionality
+ * for containers, allowing logic to be implemented based on a Container's state.
+ *
+ * @author Evan Villemez <evillemez@gmail.com>
+ *
+ */
+interface IntrospectableContainerInterface extends ContainerInterface
+{
+    /**
+     * Check for whether or not a service has been initialized.
+     *
+     * @param string $id
+     * 
+     * @return Boolean true if the service has been initialized, false otherwise
+     *
+     */
+    function initialized($id);
+    
+}
\ No newline at end of file
diff --git a/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php b/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php
index 9d38be2450419..1be51061446bd 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/ContainerTest.php
@@ -193,6 +193,18 @@ public function testHas()
         $this->assertTrue($sc->has('foo.baz'), '->has() returns true if a get*Method() is defined');
     }
 
+    /**
+     * @covers Symfony\Component\DependencyInjection\Container::initialized
+     */
+    public function testInitialized()
+    {
+        $sc = new ProjectServiceContainer();
+        $sc->set('foo', new \stdClass());
+        $this->assertTrue($sc->initialized('foo'), '->initialized() returns true if service is loaded');
+        $this->assertFalse($sc->initialized('foo1'), '->initialized() returns false if service is not loaded');
+        $this->assertFalse($sc->initialized('bar'), '->initialized() returns false if a service is defined, but not currently loaded');
+    }
+
     public function testEnterLeaveCurrentScope()
     {
         $container = new ProjectServiceContainer();