diff --git a/src/KeyRequestHandler.js b/src/KeyRequestHandler.js
new file mode 100644
index 0000000000..1da4922153
--- /dev/null
+++ b/src/KeyRequestHandler.js
@@ -0,0 +1,138 @@
+/*
+Copyright 2017 Vector Creations 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.
+*/
+
+import sdk from './index';
+import Modal from './Modal';
+
+export default class KeyRequestHandler {
+    constructor(matrixClient) {
+        this._matrixClient = matrixClient;
+
+        // the user/device for which we currently have a dialog open
+        this._currentUser = null;
+        this._currentDevice = null;
+
+        // userId -> deviceId -> [keyRequest]
+        this._pendingKeyRequests = Object.create(null);
+    }
+
+    handleKeyRequest(keyRequest) {
+        const userId = keyRequest.userId;
+        const deviceId = keyRequest.deviceId;
+        const requestId = keyRequest.requestId;
+
+        if (!this._pendingKeyRequests[userId]) {
+            this._pendingKeyRequests[userId] = Object.create(null);
+        }
+        if (!this._pendingKeyRequests[userId][deviceId]) {
+            this._pendingKeyRequests[userId][deviceId] = [];
+        }
+
+        // check if we already have this request
+        const requests = this._pendingKeyRequests[userId][deviceId];
+        if (requests.find((r) => r.requestId === requestId)) {
+            console.log("Already have this key request, ignoring");
+            return;
+        }
+
+        requests.push(keyRequest);
+
+        if (this._currentUser) {
+            // ignore for now
+            console.log("Key request, but we already have a dialog open");
+            return;
+        }
+
+        this._processNextRequest();
+    }
+
+    handleKeyRequestCancellation(cancellation) {
+        // see if we can find the request in the queue
+        const userId = cancellation.userId;
+        const deviceId = cancellation.deviceId;
+        const requestId = cancellation.requestId;
+
+        if (userId === this._currentUser && deviceId === this._currentDevice) {
+            console.log(
+                "room key request cancellation for the user we currently have a"
+                + " dialog open for",
+            );
+            // TODO: update the dialog. For now, we just ignore the
+            // cancellation.
+            return;
+        }
+
+        if (!this._pendingKeyRequests[userId]) {
+            return;
+        }
+        const requests = this._pendingKeyRequests[userId][deviceId];
+        if (!requests) {
+            return;
+        }
+        const idx = requests.findIndex((r) => r.requestId === requestId);
+        if (idx < 0) {
+            return;
+        }
+        console.log("Forgetting room key request");
+        requests.splice(idx, 1);
+        if (requests.length === 0) {
+            delete this._pendingKeyRequests[userId][deviceId];
+            if (Object.keys(this._pendingKeyRequests[userId]).length === 0) {
+                delete this._pendingKeyRequests[userId];
+            }
+        }
+    }
+
+    _processNextRequest() {
+        const userId = Object.keys(this._pendingKeyRequests)[0];
+        if (!userId) {
+            return;
+        }
+        const deviceId = Object.keys(this._pendingKeyRequests[userId])[0];
+        if (!deviceId) {
+            return;
+        }
+        console.log(`Starting KeyShareDialog for ${userId}:${deviceId}`);
+
+        const finished = (r) => {
+            this._currentUser = null;
+            this._currentDevice = null;
+
+            if (r) {
+                for (const req of this._pendingKeyRequests[userId][deviceId]) {
+                    req.share();
+                }
+            }
+            delete this._pendingKeyRequests[userId][deviceId];
+            if (Object.keys(this._pendingKeyRequests[userId]).length === 0) {
+                delete this._pendingKeyRequests[userId];
+            }
+
+            this._processNextRequest();
+        };
+
+        const KeyShareDialog = sdk.getComponent("dialogs.KeyShareDialog");
+        Modal.createDialog(KeyShareDialog, {
+            matrixClient: this._matrixClient,
+            userId: userId,
+            deviceId: deviceId,
+            onFinished: finished,
+        });
+        this._currentUser = userId;
+        this._currentDevice = deviceId;
+    }
+}
+
diff --git a/src/components/structures/MatrixChat.js b/src/components/structures/MatrixChat.js
index ef6260c5b9..97a0962741 100644
--- a/src/components/structures/MatrixChat.js
+++ b/src/components/structures/MatrixChat.js
@@ -41,6 +41,7 @@ import PageTypes from '../../PageTypes';
 
 import createRoom from "../../createRoom";
 import * as UDEHandler from '../../UnknownDeviceErrorHandler';
+import KeyRequestHandler from '../../KeyRequestHandler';
 import { _t, getCurrentLanguage } from '../../languageHandler';
 
 /** constants for MatrixChat.state.view */
@@ -1084,6 +1085,14 @@ module.exports = React.createClass({
                 }
             }
         });
+
+        const krh = new KeyRequestHandler(cli);
+        cli.on("crypto.roomKeyRequest", (req) => {
+            krh.handleKeyRequest(req);
+        });
+        cli.on("crypto.roomKeyRequestCancellation", (req) => {
+            krh.handleKeyRequestCancellation(req);
+        });
     },
 
     showScreen: function(screen, params) {
diff --git a/src/components/views/dialogs/KeyShareDialog.js b/src/components/views/dialogs/KeyShareDialog.js
new file mode 100644
index 0000000000..61391d281c
--- /dev/null
+++ b/src/components/views/dialogs/KeyShareDialog.js
@@ -0,0 +1,172 @@
+/*
+Copyright 2017 Vector Creations 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.
+*/
+
+import Modal from '../../../Modal';
+import React from 'react';
+import sdk from '../../../index';
+
+import { _t } from '../../../languageHandler';
+
+/**
+ * Dialog which asks the user whether they want to share their keys with
+ * an unverified device.
+ *
+ * onFinished is called with `true` if the key should be shared, `false` if it
+ * should not, and `undefined` if the dialog is cancelled. (In other words:
+ * truthy: do the key share. falsy: don't share the keys).
+ */
+export default React.createClass({
+    propTypes: {
+        matrixClient: React.PropTypes.object.isRequired,
+        userId: React.PropTypes.string.isRequired,
+        deviceId: React.PropTypes.string.isRequired,
+        onFinished: React.PropTypes.func.isRequired,
+    },
+
+    getInitialState: function() {
+        return {
+            deviceInfo: null,
+            wasNewDevice: false,
+        };
+    },
+
+    componentDidMount: function() {
+        this._unmounted = false;
+        const userId = this.props.userId;
+        const deviceId = this.props.deviceId;
+
+        // give the client a chance to refresh the device list
+        this.props.matrixClient.downloadKeys([userId], false).then((r) => {
+            if (this._unmounted) { return; }
+
+            const deviceInfo = r[userId][deviceId];
+
+            if(!deviceInfo) {
+                console.warn(`No details found for device ${userId}:${deviceId}`);
+
+                this.props.onFinished(false);
+                return;
+            }
+
+            const wasNewDevice = !deviceInfo.isKnown();
+
+            this.setState({
+                deviceInfo: deviceInfo,
+                wasNewDevice: wasNewDevice,
+            });
+
+            // if the device was new before, it's not any more.
+            if (wasNewDevice) {
+                this.props.matrixClient.setDeviceKnown(
+                    userId,
+                    deviceId,
+                    true,
+                );
+            }
+        }).done();
+    },
+
+    componentWillUnmount: function() {
+        this._unmounted = true;
+    },
+
+
+    _onVerifyClicked: function() {
+        const DeviceVerifyDialog = sdk.getComponent('views.dialogs.DeviceVerifyDialog');
+
+        console.log("KeyShareDialog: Starting verify dialog");
+        Modal.createDialog(DeviceVerifyDialog, {
+            userId: this.props.userId,
+            device: this.state.deviceInfo,
+            onFinished: (verified) => {
+                if (verified) {
+                    // can automatically share the keys now.
+                    this.props.onFinished(true);
+                }
+            },
+        });
+    },
+
+    _onShareClicked: function() {
+        console.log("KeyShareDialog: User clicked 'share'");
+        this.props.onFinished(true);
+    },
+
+    _onIgnoreClicked: function() {
+        console.log("KeyShareDialog: User clicked 'ignore'");
+        this.props.onFinished(false);
+    },
+
+    _renderContent: function() {
+        const displayName = this.state.deviceInfo.getDisplayName() ||
+            this.state.deviceInfo.deviceId;
+
+        let text;
+        if (this.state.wasNewDevice) {
+            text = "You added a new device '%(displayName)s', which is"
+                + " requesting encryption keys.";
+        } else {
+            text = "Your unverified device '%(displayName)s' is requesting"
+                + " encryption keys.";
+        }
+        text = _t(text, {displayName: displayName});
+
+        return (
+            <div>
+                <p>{text}</p>
+
+                <div className="mx_Dialog_buttons">
+                    <button onClick={this._onVerifyClicked}>
+                        {_t('Start verification')}
+                    </button>
+                    <button onClick={this._onShareClicked}>
+                        {_t('Share without verifying')}
+                    </button>
+                    <button onClick={this._onIgnoreClicked}>
+                        {_t('Ignore request')}
+                    </button>
+                </div>
+            </div>
+        );
+    },
+
+    render: function() {
+        const BaseDialog = sdk.getComponent('views.dialogs.BaseDialog');
+        const Spinner = sdk.getComponent('views.elements.Spinner');
+
+        let content;
+
+        if (this.state.deviceInfo) {
+            content = this._renderContent();
+        } else {
+            content = (
+                <div>
+                    <p>{_t('Loading device info...')}</p>
+                    <Spinner />
+                </div>
+            );
+        }
+
+        return (
+            <BaseDialog className='mx_KeyShareRequestDialog'
+                onFinished={this.props.onFinished}
+                title={_t('Encryption key request')}
+            >
+                {content}
+            </BaseDialog>
+        );
+    },
+});
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index e7f8199f9c..973edcca41 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -911,5 +911,11 @@
   "Authentication check failed: incorrect password?": "Authentication check failed: incorrect password?",
   "Disable Peer-to-Peer for 1:1 calls": "Disable Peer-to-Peer for 1:1 calls",
   "Do you want to set an email address?": "Do you want to set an email address?",
-  "This will allow you to reset your password and receive notifications.": "This will allow you to reset your password and receive notifications."
+  "This will allow you to reset your password and receive notifications.": "This will allow you to reset your password and receive notifications.",
+  "Start verification": "Start verification",
+  "Share without verifying": "Share without verifying",
+  "Ignore request": "Ignore request",
+  "You added a new device '%(displayName)s', which is requesting encryption keys.": "You added a new device '%(displayName)s', which is requesting encryption keys.",
+  "Your unverified device '%(displayName)s' is requesting encryption keys.": "Your unverified device '%(displayName)s' is requesting encryption keys.",
+  "Encryption key request": "Encryption key request"
 }