diff --git a/src/rest/creator.js b/src/rest/creator.js
index 05976552d0..9090a21e70 100644
--- a/src/rest/creator.js
+++ b/src/rest/creator.js
@@ -18,6 +18,7 @@ const util = require('util');
 const exec = util.promisify(require('child_process').exec);
 const request = require('request-promise-native');
 const RestSession = require('./session');
+const RestMultiSession = require('./multi');
 
 module.exports = class RestSessionCreator {
     constructor(synapseSubdir, hsUrl, cwd) {
@@ -26,6 +27,12 @@ module.exports = class RestSessionCreator {
         this.cwd = cwd;
     }
 
+    async createSessionRange(usernames, password) {
+        const sessionPromises = usernames.map((username) => this.createSession(username, password));
+        const sessions = await Promise.all(sessionPromises);
+        return new RestMultiSession(sessions);
+    }
+
     async createSession(username, password) {
         await this._register(username, password);
         const authResult = await this._authenticate(username, password);
diff --git a/src/rest/multi.js b/src/rest/multi.js
new file mode 100644
index 0000000000..12ebe9d4ab
--- /dev/null
+++ b/src/rest/multi.js
@@ -0,0 +1,61 @@
+/*
+Copyright 2018 New Vector 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.
+*/
+
+const request = require('request-promise-native');
+const RestRoom = require('./room');
+const {approveConsent} = require('./consent');
+
+module.exports = class RestMultiSession {
+    constructor(sessions) {
+        this.sessions = sessions;
+    }
+
+    slice(start, end) {
+        return new RestMultiSession(this.sessions.slice(start, end));
+    }
+
+    pop(userName) {
+        const idx = this.sessions.findIndex((s) => s.userName() === userName);
+        if(idx === -1) {
+            throw new Error(`user ${userName} not found`);
+        }
+        const session = this.sessions.splice(idx, 1)[0];
+        return session;
+    }
+
+    async setDisplayName(fn) {
+        await Promise.all(this.sessions.map((s) => s.setDisplayName(fn(s))));
+    }
+
+    async join(roomId) {
+        const rooms = await Promise.all(this.sessions.map((s) => s.join(roomId)));
+        return new RestMultiRoom(rooms);
+    }
+}
+
+class RestMultiRoom {
+    constructor(rooms) {
+        this.rooms = rooms;
+    }
+
+    async talk(message) {
+        await Promise.all(this.rooms.map((r) => r.talk(message)));
+    }
+
+    async leave() {
+        await Promise.all(this.rooms.map((r) => r.leave()));
+    }
+}
diff --git a/src/rest/room.js b/src/rest/room.js
index b7da1789ff..d8de958a27 100644
--- a/src/rest/room.js
+++ b/src/rest/room.js
@@ -20,12 +20,12 @@ const uuidv4 = require('uuid/v4');
 module.exports = class RestRoom {
     constructor(session, roomId) {
         this.session = session;
-        this.roomId = roomId;
+        this._roomId = roomId;
     }
 
     async talk(message) {
         const txId = uuidv4();
-        await this.session._put(`/rooms/${this.roomId}/send/m.room.message/${txId}`, {
+        await this.session._put(`/rooms/${this._roomId}/send/m.room.message/${txId}`, {
             "msgtype": "m.text",
             "body": message
         });
@@ -33,10 +33,10 @@ module.exports = class RestRoom {
     }
 
     async leave() {
-        await this.session._post(`/rooms/${this.roomId}/leave`);
+        await this.session._post(`/rooms/${this._roomId}/leave`);
     }
 
-    id() {
-        return this.roomId;
+    roomId() {
+        return this._roomId;
     }
 }
diff --git a/src/rest/session.js b/src/rest/session.js
index caa10a430b..44be15c3ff 100644
--- a/src/rest/session.js
+++ b/src/rest/session.js
@@ -23,38 +23,12 @@ module.exports = class RestSession {
         this.credentials = credentials;
     }
 
-    _post(csApiPath, body) {
-        return this._request("POST", csApiPath, body);
+    userId() {
+        return this.credentials.userId;
     }
 
-    _put(csApiPath, body) {
-        return this._request("PUT", csApiPath, body);
-    }
-
-    async _request(method, csApiPath, body) {
-        try {
-            const responseBody = await request({
-                url: `${this.credentials.hsUrl}/_matrix/client/r0${csApiPath}`,
-                method,
-                headers: {
-                    "Authorization": `Bearer ${this.credentials.accessToken}`
-                },
-                json: true,
-                body
-            });
-            return responseBody;
-
-        } catch(err) {
-            const responseBody = err.response.body;
-            if (responseBody.errcode === 'M_CONSENT_NOT_GIVEN') {
-                await approveConsent(responseBody.consent_uri);
-                return this._request(method, csApiPath, body);
-            } else if(responseBody && responseBody.error) {
-                throw new Error(`${method} ${csApiPath}: ${responseBody.error}`);
-            } else {
-                throw new Error(`${method} ${csApiPath}: ${err.response.statusCode}`);
-            }
-        }
+    userName() {
+        return this.credentials.userId.split(":")[0].substr(1);
     }
 
     async setDisplayName(displayName) {
@@ -90,4 +64,38 @@ module.exports = class RestSession {
         const {room_id} = await this._post(`/createRoom`, body);
         return new RestRoom(this, room_id);
     }
+
+    _post(csApiPath, body) {
+        return this._request("POST", csApiPath, body);
+    }
+
+    _put(csApiPath, body) {
+        return this._request("PUT", csApiPath, body);
+    }
+
+    async _request(method, csApiPath, body) {
+        try {
+            const responseBody = await request({
+                url: `${this.credentials.hsUrl}/_matrix/client/r0${csApiPath}`,
+                method,
+                headers: {
+                    "Authorization": `Bearer ${this.credentials.accessToken}`
+                },
+                json: true,
+                body
+            });
+            return responseBody;
+
+        } catch(err) {
+            const responseBody = err.response.body;
+            if (responseBody.errcode === 'M_CONSENT_NOT_GIVEN') {
+                await approveConsent(responseBody.consent_uri);
+                return this._request(method, csApiPath, body);
+            } else if(responseBody && responseBody.error) {
+                throw new Error(`${method} ${csApiPath}: ${responseBody.error}`);
+            } else {
+                throw new Error(`${method} ${csApiPath}: ${err.response.statusCode}`);
+            }
+        }
+    }
 }