diff --git a/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
index 251b920..5bb9564 100644
--- a/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
@@ -123,7 +123,7 @@ public function onRespond(FilterResponseEvent $event) {
       $response->headers->set('X-Drupal-Cache-Contexts', implode(' ', $this->cacheContextsManager->optimizeTokens($response_cacheability->getCacheContexts())));
     }
 
-    $is_cacheable = ($this->requestPolicy->check($request) === RequestPolicyInterface::ALLOW) && ($this->responsePolicy->check($response, $request) !== ResponsePolicyInterface::DENY);
+    $is_cacheable = ($response instanceof CacheableResponseInterface) && ($this->requestPolicy->check($request) === RequestPolicyInterface::ALLOW) && ($this->responsePolicy->check($response, $request) !== ResponsePolicyInterface::DENY);
 
     // Add headers necessary to specify whether the response should be cached by
     // proxies and/or the browser.
diff --git a/core/modules/page_cache/src/Tests/PageCacheTest.php b/core/modules/page_cache/src/Tests/PageCacheTest.php
index e97a1b4..f4bbd89 100644
--- a/core/modules/page_cache/src/Tests/PageCacheTest.php
+++ b/core/modules/page_cache/src/Tests/PageCacheTest.php
@@ -204,7 +204,7 @@ function testPageCache() {
     // Fill the cache.
     $this->drupalGet('system-test/set-header', array('query' => array('name' => 'Foo', 'value' => 'bar')));
     $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie,accept-encoding', 'Vary header was sent.');
+    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie', 'Vary header was sent.');
     // Symfony's Response logic determines a specific order for the subvalues
     // of the Cache-Control header, even if they are explicitly passed in to
     // the response header bag in a different order.
@@ -215,7 +215,7 @@ function testPageCache() {
     // Check cache.
     $this->drupalGet('system-test/set-header', array('query' => array('name' => 'Foo', 'value' => 'bar')));
     $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie,accept-encoding', 'Vary: Cookie header was sent.');
+    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie', 'Vary: Cookie header was sent.');
     $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
     $this->assertEqual($this->drupalGetHeader('Expires'), 'Sun, 19 Nov 1978 05:00:00 GMT', 'Expires header was sent.');
     $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
@@ -224,7 +224,7 @@ function testPageCache() {
     $this->drupalGet('system-test/set-header', array('query' => array('name' => 'Expires', 'value' => 'Fri, 19 Nov 2008 05:00:00 GMT')));
     $this->assertEqual($this->drupalGetHeader('Expires'), 'Fri, 19 Nov 2008 05:00:00 GMT', 'Default header was replaced.');
     $this->drupalGet('system-test/set-header', array('query' => array('name' => 'Vary', 'value' => 'User-Agent')));
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'user-agent,accept-encoding', 'Default header was replaced.');
+    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'user-agent', 'Default header was replaced.');
 
     // Check that authenticated users bypass the cache.
     $user = $this->drupalCreateUser();
@@ -406,4 +406,35 @@ public function testFormImmutability() {
     $this->assertText("Immutable: FALSE", "Form is not immutable,");
   }
 
+  /**
+   * Tests the difference between having a controller return a Response object
+   * versus returning a CacheableReponse
+   */
+  public function testCacheableResponseResponses() {
+    $config = $this->config('system.performance');
+    $config->set('cache.page.max_age', 300);
+    $config->save();
+
+    // Try to fill the cache.
+    $this->drupalGet('/system-test/respond-reponse');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
+    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'must-revalidate, no-cache, post-check=0, pre-check=0, private', 'Cache-Control header was sent');
+
+    // still not cached, uncacheable response
+    $this->drupalGet('/system-test/respond-reponse');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
+    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'must-revalidate, no-cache, post-check=0, pre-check=0, private', 'Cache-Control header was sent');
+
+    // Try to fill the cache.
+    $this->drupalGet('/system-test/respond-cacheable-reponse');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
+    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+
+    // still not cached, uncacheable response
+    $this->drupalGet('/system-test/respond-cacheable-reponse');
+    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
+    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+
+  }
+
 }
diff --git a/core/modules/rest/src/RequestHandler.php b/core/modules/rest/src/RequestHandler.php
index ee4b890..78b9ecb 100644
--- a/core/modules/rest/src/RequestHandler.php
+++ b/core/modules/rest/src/RequestHandler.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\rest;
 
+use Drupal\Core\Cache\CacheableResponse;
 use Drupal\Core\Render\RenderContext;
 use Drupal\Core\Routing\RouteMatchInterface;
 use Symfony\Component\DependencyInjection\ContainerAwareInterface;
@@ -67,7 +68,7 @@ public function handle(RouteMatchInterface $route_match, Request $request) {
         catch (UnexpectedValueException $e) {
           $error['error'] = $e->getMessage();
           $content = $serializer->serialize($error, $format);
-          return new Response($content, 400, array('Content-Type' => $request->getMimeType($format)));
+          return new CacheableResponse($content, 400, array('Content-Type' => $request->getMimeType($format)));
         }
       }
       else {
@@ -100,7 +101,7 @@ public function handle(RouteMatchInterface $route_match, Request $request) {
       // Add the default content type, but only if the headers from the
       // exception have not specified it already.
       $headers = $e->getHeaders() + array('Content-Type' => $request->getMimeType($format));
-      return new Response($content, $e->getStatusCode(), $headers);
+      return new CacheableResponse($content, $e->getStatusCode(), $headers);
     }
 
     // Serialize the outgoing data for the response, if available.
diff --git a/core/modules/system/tests/modules/system_test/src/Controller/SystemTestController.php b/core/modules/system/tests/modules/system_test/src/Controller/SystemTestController.php
index 5ac7ca0..9847adf 100644
--- a/core/modules/system/tests/modules/system_test/src/Controller/SystemTestController.php
+++ b/core/modules/system/tests/modules/system_test/src/Controller/SystemTestController.php
@@ -8,6 +8,7 @@
 namespace Drupal\system_test\Controller;
 
 use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Cache\CacheableResponse;
 use Drupal\Core\Controller\ControllerBase;
 use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Session\AccountInterface;
@@ -241,13 +242,21 @@ public function authorizeInit($page_title) {
    */
   public function setHeader(Request $request) {
     $query = $request->query->all();
-    $response = new Response();
+    $response = new CacheableResponse();
     $response->headers->set($query['name'], $query['value']);
     $response->setContent($this->t('The following header was set: %name: %value', array('%name' => $query['name'], '%value' => $query['value'])));
 
     return $response;
   }
 
+  public function respondWithReponse(Request $request) {
+    return new Response('test');
+  }
+
+  public function respondWithCacheableReponse(Request $request) {
+    return new CacheableResponse('test');
+  }
+
   /**
    * A simple page callback which adds a register shutdown function.
    */
diff --git a/core/modules/system/tests/modules/system_test/system_test.routing.yml b/core/modules/system/tests/modules/system_test/system_test.routing.yml
index ecb9921..94a1bef 100644
--- a/core/modules/system/tests/modules/system_test/system_test.routing.yml
+++ b/core/modules/system/tests/modules/system_test/system_test.routing.yml
@@ -129,3 +129,17 @@ system_test.permission_dependent_route_access:
     _controller: '\Drupal\system_test\Controller\SystemTestController::mainContentFallback'
   requirements:
     _permission: 'pet llamas'
+
+system_test.respond_response:
+  path: '/system-test/respond-reponse'
+  defaults:
+    _controller: '\Drupal\system_test\Controller\SystemTestController::respondWithReponse'
+  requirements:
+    _access: 'TRUE'
+
+system_test.respond_cacheable_response:
+  path: '/system-test/respond-cacheable-reponse'
+  defaults:
+    _controller: '\Drupal\system_test\Controller\SystemTestController::respondWithCacheableReponse'
+  requirements:
+    _access: 'TRUE'