diff --git a/specification/modules/dm.rst b/specification/modules/dm.rst
new file mode 100644
index 00000000..4747bd48
--- /dev/null
+++ b/specification/modules/dm.rst
@@ -0,0 +1,57 @@
+.. Copyright 2016 OpenMarket Ltd
+..
+.. Licensed under the Apache License, Version 2.0 (the "License");
+.. you may not use this file except in compliance with the License.
+.. You may obtain a copy of the License at
+..
+..     http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Direct Messaging
+================
+
+.. _module:dm:
+
+All communications over Matrix happens within a room. It is sometimes
+desireable to offer users the concept of speaking directly to one
+particular person. This module defines a way of marking certain rooms
+as 'direct chats' with a given person. This does not restrict the chat
+to being between exactly two people since this would preclude the
+presence of automated 'bot' users or even a 'personal assistant' who is
+able to answer direct messages on behalf of the user in their absence.
+
+A room may not necessarily be considered 'direct' by all members of the
+room, but a signalling mechanism exists to propagate the information of
+whether a chat is 'direct' to an invitee. The invitee's client may
+use this flag to automatically mark the room as a direct message but
+this is not required: it may for example, prompt the user, ignore the
+flag altogether.
+
+Events
+------
+
+A map of which rooms are considered 'direct' rooms for specific users
+is kept in  ``account_data`` in an event of type ``m.direct``. The
+content of this event is an object where the keys are the user IDs
+and values are lists of room ID strings of the 'direct' rooms for
+that user ID.
+
+Example::
+
+    {
+        "@bob:example.com": [
+            "!abcdefgh:example.com",
+            "!hgfedcba:example.com"
+        ]
+    }
+
+
+When creating a room, the ``is_direct`` flag may be specified to signal
+to the invitee that this is a direct chat. See
+`GET /_matrix/client/unstable/initialSync`_. This flag appears as
+``is_direct`` in the member event: see `m.room.member`_.
diff --git a/specification/targets.yaml b/specification/targets.yaml
index 6cbfa917..c63db5a6 100644
--- a/specification/targets.yaml
+++ b/specification/targets.yaml
@@ -53,6 +53,7 @@ groups:  # reusable blobs of files when prefixed with 'group:'
     - modules/admin.rst
     - modules/event_context.rst
     - modules/cas_login.rst
+    - modules/dm.rst
 
 
 title_styles: ["=", "-", "~", "+", "^", "`", "@", ":"]