diff --git a/nrm/messaging.py b/nrm/messaging.py
index 8a266bfc6ca4f8d4e912411d0b3f81a145fb1bf9..6ff8e0724932327ccab0e3e766e8661f91e04ef4 100644
--- a/nrm/messaging.py
+++ b/nrm/messaging.py
@@ -18,7 +18,7 @@ logger = logging.getLogger('nrm')
 # list of APIs supported by this messaging layer. Each message is
 # indexed by its intended api user and the type of the message, along with
 # basic field type information.
-APIS = ['up_rpc_req', 'up_rpc_rep', 'up_pub']
+APIS = ['up_rpc_req', 'up_rpc_rep', 'up_pub', 'down_event']
 MSGFORMATS = {k: {} for k in APIS}
 MSGFORMATS['up_rpc_req'] = {'list': {},
                             'run': {'manifest': basestring,
@@ -47,6 +47,13 @@ MSGFORMATS['up_pub'] = {'power': {'total': int, 'limit': float},
                         'container_exit': {'container_uuid': basestring,
                                            'profile_data': dict},
                         }
+MSGFORMATS['down_event'] = {'application_start':
+                            {'container_uuid': basestring,
+                             'application_uuid': basestring},
+                            'application_exit':
+                            {'application_uuid': basestring},
+                            'progress': {'payload': int},
+                            }
 
 # Mirror of the message formats, using namedtuples as the actual transport
 # for users of this messaging layer.
@@ -223,3 +230,20 @@ class UpstreamPubClient(object):
         self.stream = zmqstream.ZMQStream(self.socket)
         self.callback = callback
         self.stream.on_recv(self.do_recv_callback)
+
+
+class DownstreamEventServer(UpstreamRPCServer):
+
+    """Implements the message layer server for the downstream event API."""
+
+    def sendmsg(self, msg, client_uuid):
+        assert False, "Cannot send message from this side of the event stream."
+
+
+class DownstreamEventClient(UpstreamRPCClient):
+
+    """Implements the message layer client for the downstream event API."""
+
+    def recvmsg(self):
+        assert False, \
+            "Cannot receive messages from this side of the event stream."
diff --git a/test/test_messaging.py b/test/test_messaging.py
index 7df4479ef1aa0ae0c0ab391447cc19d5754e83bd..8f3384707ad78e21427f402212844924ede354cd 100644
--- a/test/test_messaging.py
+++ b/test/test_messaging.py
@@ -28,6 +28,18 @@ def upstream_pub_client():
     return nrm.messaging.UpstreamPubClient("ipc:///tmp/nrm-pytest-pub")
 
 
+@pytest.fixture
+def downstream_event_server():
+    """Fixture for a server handle on the downstream event API"""
+    return nrm.messaging.DownstreamEventServer("ipc:///tmp/nrm-pytest-down")
+
+
+@pytest.fixture
+def downstream_event_client():
+    """Fixture for a client handle on the downstream event API"""
+    return nrm.messaging.DownstreamEventClient("ipc:///tmp/nrm-pytest-down")
+
+
 @pytest.fixture
 def dummy_msg():
     """Fixture for a dummy valid message."""
@@ -89,3 +101,26 @@ def test_pub_client_recv(upstream_pub_server, upstream_pub_client, dummy_msg):
     upstream_pub_server.sendmsg(dummy_msg)
     msg = upstream_pub_client.recvmsg()
     assert msg == dummy_msg
+
+
+def test_down_connection(downstream_event_client, downstream_event_server):
+    downstream_event_client.wait_connected()
+
+
+def test_down_event_send_recv(downstream_event_client, downstream_event_server,
+                              dummy_msg):
+    downstream_event_client.sendmsg(dummy_msg)
+    msg, client = downstream_event_server.recvmsg()
+    assert msg == dummy_msg
+    assert client == downstream_event_client.uuid
+
+
+def test_down_event_server_callback(downstream_event_client,
+                                    downstream_event_server,
+                                    dummy_msg, dummy_daemon):
+    downstream_event_server.setup_recv_callback(dummy_daemon.callback)
+    frames = [downstream_event_client.uuid, nrm.messaging.msg2wire(dummy_msg)]
+    downstream_event_server.do_recv_callback(frames)
+    assert dummy_daemon.called
+    assert dummy_daemon.msg == dummy_msg
+    assert dummy_daemon.client == downstream_event_client.uuid