diff --git a/gcloud/pubsub/test_topic.py b/gcloud/pubsub/test_topic.py
index 849fa60ec0aa..d66cf6d68c05 100644
--- a/gcloud/pubsub/test_topic.py
+++ b/gcloud/pubsub/test_topic.py
@@ -38,17 +38,22 @@ def test_ctor_wo_inferred_project_or_connection(self):
         self.assertEqual(topic.full_name,
                          'projects/%s/topics/%s' % (PROJECT, TOPIC_NAME))
         self.assertTrue(topic.connection is conn)
+        self.assertFalse(topic.timestamp_messages)
 
-    def test_ctor_w_explicit_project_and_connection(self):
+    def test_ctor_w_explicit_project_connection_and_timestamp(self):
         TOPIC_NAME = 'topic_name'
         PROJECT = 'PROJECT'
         conn = _Connection()
-        topic = self._makeOne(TOPIC_NAME, project=PROJECT, connection=conn)
+        topic = self._makeOne(TOPIC_NAME,
+                              project=PROJECT,
+                              connection=conn,
+                              timestamp_messages=True)
         self.assertEqual(topic.name, TOPIC_NAME)
         self.assertEqual(topic.project, PROJECT)
         self.assertEqual(topic.full_name,
                          'projects/%s/topics/%s' % (PROJECT, TOPIC_NAME))
         self.assertTrue(topic.connection is conn)
+        self.assertTrue(topic.timestamp_messages)
 
     def test_from_api_repr_wo_connection(self):
         from gcloud.pubsub._testing import _monkey_defaults
@@ -146,6 +151,67 @@ def test_publish_single_bytes_wo_attrs(self):
         self.assertEqual(req['path'], '/%s:publish' % PATH)
         self.assertEqual(req['data'], {'messages': [MESSAGE]})
 
+    def test_publish_single_bytes_wo_attrs_w_add_timestamp(self):
+        import base64
+        import datetime
+        from gcloud.pubsub import topic as MUT
+        from gcloud._testing import _Monkey
+        NOW = datetime.datetime.utcnow()
+
+        def _utcnow():
+            return NOW
+
+        TOPIC_NAME = 'topic_name'
+        PROJECT = 'PROJECT'
+        PAYLOAD = b'This is the message text'
+        B64 = base64.b64encode(PAYLOAD).decode('ascii')
+        MSGID = 'DEADBEEF'
+        MESSAGE = {'data': B64,
+                   'attributes': {'timestamp': '%sZ' % NOW.isoformat()}}
+        PATH = 'projects/%s/topics/%s' % (PROJECT, TOPIC_NAME)
+        conn = _Connection({'messageIds': [MSGID]})
+        topic = self._makeOne(TOPIC_NAME, project=PROJECT, connection=conn,
+                              timestamp_messages=True)
+        with _Monkey(MUT, _NOW=_utcnow):
+            msgid = topic.publish(PAYLOAD)
+        self.assertEqual(msgid, MSGID)
+        self.assertEqual(len(conn._requested), 1)
+        req = conn._requested[0]
+        self.assertEqual(req['method'], 'POST')
+        self.assertEqual(req['path'], '/%s:publish' % PATH)
+        self.assertEqual(req['data'], {'messages': [MESSAGE]})
+
+    def test_publish_single_bytes_w_add_timestamp_w_ts_in_attrs(self):
+        import base64
+        import datetime
+        from gcloud.pubsub import topic as MUT
+        from gcloud._testing import _Monkey
+        NOW = datetime.datetime.utcnow()
+
+        def _utcnow():  # pragma: NO COVER
+            return NOW
+
+        TOPIC_NAME = 'topic_name'
+        PROJECT = 'PROJECT'
+        PAYLOAD = b'This is the message text'
+        B64 = base64.b64encode(PAYLOAD).decode('ascii')
+        MSGID = 'DEADBEEF'
+        OVERRIDE = '2015-04-10T16:46:22.868399Z'
+        MESSAGE = {'data': B64,
+                   'attributes': {'timestamp': OVERRIDE}}
+        PATH = 'projects/%s/topics/%s' % (PROJECT, TOPIC_NAME)
+        conn = _Connection({'messageIds': [MSGID]})
+        topic = self._makeOne(TOPIC_NAME, project=PROJECT, connection=conn,
+                              timestamp_messages=True)
+        with _Monkey(MUT, _NOW=_utcnow):
+            msgid = topic.publish(PAYLOAD, timestamp=OVERRIDE)
+        self.assertEqual(msgid, MSGID)
+        self.assertEqual(len(conn._requested), 1)
+        req = conn._requested[0]
+        self.assertEqual(req['method'], 'POST')
+        self.assertEqual(req['path'], '/%s:publish' % PATH)
+        self.assertEqual(req['data'], {'messages': [MESSAGE]})
+
     def test_publish_single_w_attrs(self):
         import base64
         TOPIC_NAME = 'topic_name'
diff --git a/gcloud/pubsub/topic.py b/gcloud/pubsub/topic.py
index 9243b895a536..67814fdb7ec2 100644
--- a/gcloud/pubsub/topic.py
+++ b/gcloud/pubsub/topic.py
@@ -15,11 +15,14 @@
 """Define API Topics."""
 
 import base64
+import datetime
 
 from gcloud._helpers import get_default_project
 from gcloud.exceptions import NotFound
 from gcloud.pubsub._implicit_environ import get_default_connection
 
+_NOW = datetime.datetime.utcnow
+
 
 class Topic(object):
     """Topics are targets to which messages can be published.
@@ -39,9 +42,14 @@ class Topic(object):
     :type connection: :class:gcloud.pubsub.connection.Connection
     :param connection: the connection to use.  If not passed,
                         falls back to the default inferred from the
-                        environment.
+
+    :type timestamp_messages: boolean
+    :param timestamp_messages: If true, the topic will add a ``timestamp`` key
+                               to the attributes of each published message:
+                               the value will be an RFC 3339 timestamp.
     """
-    def __init__(self, name, project=None, connection=None):
+    def __init__(self, name, project=None, connection=None,
+                 timestamp_messages=False):
         if project is None:
             project = get_default_project()
         if connection is None:
@@ -49,6 +57,7 @@ def __init__(self, name, project=None, connection=None):
         self.name = name
         self.project = project
         self.connection = connection
+        self.timestamp_messages = timestamp_messages
 
     @classmethod
     def from_api_repr(cls, resource, connection=None):
@@ -113,6 +122,8 @@ def publish(self, message, **attrs):
         :rtype: str
         :returns: message ID assigned by the server to the published message
         """
+        if self.timestamp_messages and 'timestamp' not in attrs:
+            attrs['timestamp'] = '%sZ' % _NOW().isoformat()
         message_b = base64.b64encode(message).decode('ascii')
         message_data = {'data': message_b, 'attributes': attrs}
         data = {'messages': [message_data]}