diff --git a/.travis.yml b/.travis.yml
index b416272..c66632c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,12 @@
 language: python
 python: 2.7
 sudo: false
+# TODO(issue 532): Fix syntax when 3.5 is natively available upstream
+matrix:
+  include:
+    - python: 3.5
+      env:
+      - TOX_ENV=py35
 env:
   matrix:
   - TOX_ENV=py26
diff --git a/tests/test_client.py b/tests/test_client.py
index c3a7377..9b21cf5 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -1279,18 +1279,18 @@ class BasicCredentialsTests(unittest2.TestCase):
 
     def test__do_refresh_request_non_json_failure(self):
         response = httplib2.Response({
-            'status': http_client.BAD_REQUEST,
+            'status': int(http_client.BAD_REQUEST),
         })
         content = u'Bad request'
-        error_msg = 'Invalid response %s.' % (response.status,)
+        error_msg = 'Invalid response %s.' % (int(response.status),)
         self._do_refresh_request_test_helper(response, content, error_msg)
 
     def test__do_refresh_request_basic_failure(self):
         response = httplib2.Response({
-            'status': http_client.INTERNAL_SERVER_ERROR,
+            'status': int(http_client.INTERNAL_SERVER_ERROR),
         })
         content = u'{}'
-        error_msg = 'Invalid response %s.' % (response.status,)
+        error_msg = 'Invalid response %s.' % (int(response.status),)
         self._do_refresh_request_test_helper(response, content, error_msg)
 
     def test__do_refresh_request_failure_w_json_error(self):
@@ -1828,21 +1828,21 @@ class OAuth2WebServerFlowTest(unittest2.TestCase):
         self.assertEqual(exc_manager.exception.args, (error_msg,))
 
     def test_step1_get_device_and_user_codes_non_json_failure(self):
-        status = http_client.BAD_REQUEST
+        status = int(http_client.BAD_REQUEST)
         content = 'Nope not JSON.'
         error_msg = 'Invalid response %s.' % (status,)
         self._step1_get_device_and_user_codes_fail_helper(status, content,
                                                           error_msg)
 
     def test_step1_get_device_and_user_codes_basic_failure(self):
-        status = http_client.INTERNAL_SERVER_ERROR
+        status = int(http_client.INTERNAL_SERVER_ERROR)
         content = b'{}'
         error_msg = 'Invalid response %s.' % (status,)
         self._step1_get_device_and_user_codes_fail_helper(status, content,
                                                           error_msg)
 
     def test_step1_get_device_and_user_codes_failure_w_json_error(self):
-        status = http_client.BAD_GATEWAY
+        status = int(http_client.BAD_GATEWAY)
         base_error = 'ZOMG user codes failure.'
         content = json.dumps({'error': base_error})
         error_msg = 'Invalid response %s. Error: %s' % (status, base_error)
diff --git a/tests/test_file.py b/tests/test_file.py
index 4bf56bf..3440327 100644
--- a/tests/test_file.py
+++ b/tests/test_file.py
@@ -151,13 +151,13 @@ class OAuth2ClientFileTests(unittest2.TestCase):
         access_token = '1/3w'
         token_response = {'access_token': access_token, 'expires_in': 3600}
         http = HttpMockSequence([
-            ({'status': str(http_client.UNAUTHORIZED)},
+            ({'status': str(int(http_client.UNAUTHORIZED))},
              b'Initial token expired'),
-            ({'status': str(http_client.UNAUTHORIZED)},
+            ({'status': str(int(http_client.UNAUTHORIZED))},
              b'Store token expired'),
-            ({'status': str(http_client.OK)},
+            ({'status': str(int(http_client.OK))},
              json.dumps(token_response).encode('utf-8')),
-            ({'status': str(http_client.OK)},
+            ({'status': str(int(http_client.OK))},
              b'Valid response to original request')
         ])
 
@@ -196,13 +196,13 @@ class OAuth2ClientFileTests(unittest2.TestCase):
         token_response = {'access_token': valid_access_token,
                           'expires_in': 3600}
         http = HttpMockSequence([
-            ({'status': str(http_client.UNAUTHORIZED)},
+            ({'status': str(int(http_client.UNAUTHORIZED))},
              b'Initial token expired'),
-            ({'status': str(http_client.UNAUTHORIZED)},
+            ({'status': str(int(http_client.UNAUTHORIZED))},
              b'Store token expired'),
-            ({'status': str(http_client.OK)},
+            ({'status': str(int(http_client.OK))},
              json.dumps(token_response).encode('utf-8')),
-            ({'status': str(http_client.OK)}, 'echo_request_body')
+            ({'status': str(int(http_client.OK))}, 'echo_request_body')
         ])
 
         body = six.StringIO('streaming body')
diff --git a/tox.ini b/tox.ini
index 8e94c01..5163f65 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py26,py27,py33,py34,pypy,gae,cover
+envlist = py26,py27,py33,py34,py35,pypy,gae,cover
 
 [testenv]
 basedeps = mock>=1.3.0