diff --git a/.eslintrc.json b/.eslintrc.json
index 0ad7365c35..0a80b5785c 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -31,6 +31,7 @@
         "settings": false,
         "resize": false,
         "loading": false,
+        "typing": false,
         "compose": false,
         "compose_fade": false,
         "modals": false,
diff --git a/frontend_tests/node_tests/templates.js b/frontend_tests/node_tests/templates.js
index b3a72e951f..3af5ccf85b 100644
--- a/frontend_tests/node_tests/templates.js
+++ b/frontend_tests/node_tests/templates.js
@@ -1023,6 +1023,24 @@ function render(template_name, args) {
     });
 }());
 
+(function typing_notifications() {
+    var args = {
+        users: [{
+            full_name: 'Hamlet',
+            email: 'hamlet@zulip.com',
+        }],
+    };
+
+    var html = '';
+    html += '<ul>';
+    html += render('typing_notifications', args);
+    html += '</ul>';
+
+    global.write_handlebars_output('typing_notifications', html);
+    var li = $(html).find('li:first');
+    assert.equal(li.text(), 'Hamlet is typing...');
+}());
+
 (function user_presence_rows() {
     var args = {
         users: [
diff --git a/static/js/server_events.js b/static/js/server_events.js
index e1a02f56b7..a516e84f84 100644
--- a/static/js/server_events.js
+++ b/static/js/server_events.js
@@ -234,6 +234,20 @@ function dispatch_normal_event(event) {
         }
         break;
 
+    case 'typing':
+        if (event.sender.user_id === page_params.user_id) {
+            // typing notifications are sent to the user who is typing
+            // as well as recipients; we ignore such self-generated events.
+            return;
+        }
+
+        if (event.op === 'start') {
+            typing.display_notification(event);
+        } else if (event.op === 'stop') {
+            typing.hide_notification(event);
+        }
+        break;
+
     case 'update_display_settings':
         if (event.setting_name === 'twenty_four_hour_time') {
             page_params.twenty_four_hour_time = event.setting;
diff --git a/static/js/typing.js b/static/js/typing.js
new file mode 100644
index 0000000000..fcae1c0df9
--- /dev/null
+++ b/static/js/typing.js
@@ -0,0 +1,184 @@
+var typing = (function () {
+var exports = {};
+// How long before we assume a client has gone away
+// and expire its typing status
+var TYPING_STARTED_EXPIRY_PERIOD = 15000; // 15s
+// How frequently 'still typing' notifications are sent
+// to extend the expiry
+var TYPING_STARTED_SEND_FREQUENCY = 10000; // 10s
+// How long after someone stops editing in the compose box
+// do we send a 'stopped typing' notification
+var TYPING_STOPPED_WAIT_PERIOD = 5000; // 5s
+
+var current_recipient;
+var users_currently_typing = new Dict();
+var stop_typing_timers = new Dict();
+
+// Our logic is a bit too complex to encapsulate in
+// _.throttle/_.debounce (since we need to cancel things), so we do it
+// manually.
+var stop_timer;
+var last_start_time;
+
+function send_typing_notification_ajax(recipients, operation) {
+    channel.post({
+        url: '/json/typing',
+        data: {
+            to: recipients,
+            op: operation,
+        },
+        success: function () {},
+        error: function (xhr) {
+            blueslip.warn("Failed to send typing event: " + xhr.responseText);
+        },
+    });
+}
+
+function check_and_send(operation) {
+    var compose_recipient = compose.recipient();
+    var compose_nonempty = compose.has_message_content();
+
+    // If we currently have an active typing notification out, and we
+    // want to send a stop notice, or the compose recipient changed
+    // (and implicitly we're sending a start notice), send a stop
+    // notice to the old recipient.
+    if (current_recipient !== undefined &&
+        (operation === 'stop' ||
+         current_recipient !== compose_recipient)) {
+        send_typing_notification_ajax(current_recipient, 'stop');
+        // clear the automatic stop notification timer and recipient.
+        clearTimeout(stop_timer);
+        stop_timer = undefined;
+        current_recipient = undefined;
+    }
+    if (operation === 'start') {
+        if (compose_recipient !== undefined && compose_recipient !== "" && compose_nonempty) {
+            current_recipient = compose_recipient;
+            send_typing_notification_ajax(compose_recipient, operation);
+        }
+    }
+}
+
+// Note: Because we don't make sure we send a final start notification
+// at the last time a user typed something, we require that
+// TYPING_STARTED_SEND_FREQUENCY + TYPING_STOPPED_WAIT_PERIOD <= TYPING_STARTED_EXPIRY_PERIOD
+$(document).on('input', '#new_message_content', function () {
+    // If our previous state was no typing notification, send a
+    // start-typing notice immediately.
+    var current_time = new Date();
+    if (current_recipient === undefined ||
+        current_time - last_start_time > TYPING_STARTED_SEND_FREQUENCY) {
+        last_start_time = current_time;
+        check_and_send("start");
+    }
+
+    // Then, regardless of whether we changed state, reset the
+    // stop-notification timeout to TYPING_STOPPED_WAIT_PERIOD from
+    // now, so that we'll send a stop notice exactly that long after
+    // stopping typing.
+    if (stop_timer !== undefined) {
+        // Clear an existing stop_timer, if any.
+        clearTimeout(stop_timer);
+    }
+    stop_timer = setTimeout(function () {
+        check_and_send('stop');
+    }, TYPING_STOPPED_WAIT_PERIOD);
+});
+
+// We send a stop-typing notification immediately when compose is
+// closed/cancelled
+$(document).on('compose_canceled.zulip compose_finished.zulip', function () {
+    check_and_send('stop');
+});
+
+function get_users_typing_for_narrow() {
+    if (!narrow.narrowed_to_pms()) {
+        // Narrow is neither pm-with nor is: private
+        return [];
+    }
+    if (narrow.operators()[0].operator === 'pm-with') {
+        // Get list of users typing in this conversation
+        var narrow_emails_string = narrow.operators()[0].operand;
+        var narrow_user_ids_string = people.emails_strings_to_user_ids_string(narrow_emails_string);
+        var narrow_user_ids = narrow_user_ids_string.split(',').map(function (user_id_string) {
+            return parseInt(user_id_string, 10);
+        });
+        var group = narrow_user_ids.concat([page_params.user_id]);
+        group.sort();
+        return users_currently_typing.setdefault(group, []);
+    }
+    // Get all users typing (in all private conversations with current user)
+    var all_typing_users = [];
+    users_currently_typing.each(function (users_typing) {
+        all_typing_users = all_typing_users.concat(users_typing);
+    });
+    return all_typing_users;
+}
+
+function render_notifications_for_narrow() {
+    var user_ids = get_users_typing_for_narrow();
+    var users_typing = user_ids.map(people.get_person_from_user_id);
+    if (users_typing.length === 0) {
+        $('#typing_notifications').hide();
+    } else {
+        $('#typing_notifications').html(templates.render('typing_notifications', {users: users_typing}));
+        $('#typing_notifications').show();
+    }
+}
+
+$(document).on('narrow_activated.zulip', render_notifications_for_narrow);
+$(document).on('narrow_deactivated.zulip', render_notifications_for_narrow);
+
+exports.hide_notification = function (event) {
+    var recipients = event.recipients.map(function (user) {
+        return user.user_id;
+    });
+    recipients.sort();
+
+    // If there's an existing timer for this typing notifications
+    // thread, clear it.
+    if (stop_typing_timers[recipients] !== undefined) {
+        clearTimeout(stop_typing_timers[recipients]);
+        stop_typing_timers[recipients] = undefined;
+    }
+
+    var users_typing = users_currently_typing.get(recipients);
+    var i = users_typing.indexOf(event.sender.user_id);
+    if (i !== -1) {
+        users_typing.splice(i);
+    }
+    render_notifications_for_narrow();
+};
+
+exports.display_notification = function (event) {
+    var recipients = event.recipients.map(function (user) {
+        return user.user_id;
+    });
+    recipients.sort();
+
+    event.sender.name = people.get_person_from_user_id(event.sender.user_id).full_name;
+
+    var users_typing = users_currently_typing.setdefault(recipients, []);
+    var i = users_typing.indexOf(event.sender.user_id);
+    if (i === -1) {
+        users_typing.push(event.sender.user_id);
+    }
+
+    render_notifications_for_narrow();
+    // If there's an existing timeout for this typing notifications
+    // thread, clear it.
+    if (stop_typing_timers[recipients] !== undefined) {
+        clearTimeout(stop_typing_timers[recipients]);
+    }
+    // Set a time to expire the data if the sender stops transmitting
+    stop_typing_timers[recipients] = setTimeout(function () {
+        exports.hide_notification(event);
+    }, TYPING_STARTED_EXPIRY_PERIOD);
+};
+
+return exports;
+}());
+
+if (typeof module !== 'undefined') {
+    module.exports = typing;
+}
diff --git a/static/styles/media.css b/static/styles/media.css
index 39af227d21..de845f9e27 100644
--- a/static/styles/media.css
+++ b/static/styles/media.css
@@ -68,6 +68,10 @@
         margin-right: 7px;
     }
 
+    #typing_notifications {
+        margin-right: 7px;
+    }
+
     .nav .dropdown-menu {
         min-width: 180px;
         -webkit-box-shadow: 0px 0px 5px rgba(0, 0, 0, 0.2);
@@ -162,6 +166,11 @@
         margin-left: 7px;
     }
 
+    #typing_notifications {
+        margin-right: 7px;
+        margin-left: 7px;
+    }
+
     #searchbox {
         margin-left: 42px;
     }
diff --git a/static/styles/typing_notifications.css b/static/styles/typing_notifications.css
new file mode 100644
index 0000000000..42a22f458f
--- /dev/null
+++ b/static/styles/typing_notifications.css
@@ -0,0 +1,11 @@
+#typing_notifications {
+    display: none;
+    margin-left: 10px;
+    font-style: italic;
+    color: #888;
+}
+
+#typing_notification_list {
+    list-style: none;
+    margin: 0;
+}
diff --git a/static/templates/typing_notification.handlebars b/static/templates/typing_notification.handlebars
new file mode 100644
index 0000000000..682af9e0f5
--- /dev/null
+++ b/static/templates/typing_notification.handlebars
@@ -0,0 +1 @@
+<li data-email="{{this.email}}" class="typing_notification">{{this.full_name}} is typing...</li>
diff --git a/static/templates/typing_notifications.handlebars b/static/templates/typing_notifications.handlebars
new file mode 100644
index 0000000000..516780310d
--- /dev/null
+++ b/static/templates/typing_notifications.handlebars
@@ -0,0 +1,6 @@
+{{! Typing Notifications }}
+<ul id="typing_notification_list">
+    {{#each users}}
+    {{partial "typing_notification"}}
+    {{/each}}
+</ul>
diff --git a/templates/zerver/home.html b/templates/zerver/home.html
index eeddb2b59e..72fc22bead 100644
--- a/templates/zerver/home.html
+++ b/templates/zerver/home.html
@@ -84,6 +84,8 @@
       </div>
       <div class="message_table" id="zfilt">
       </div>
+      <div id="typing_notifications">
+      </div>
       <div id="bottom_whitespace"></div>
     </div>
 
diff --git a/zproject/settings.py b/zproject/settings.py
index fe144a915b..c74d6988e7 100644
--- a/zproject/settings.py
+++ b/zproject/settings.py
@@ -705,6 +705,7 @@ PIPELINE = {
                 'styles/pygments.css',
                 'styles/thirdparty-fonts.css',
                 'styles/media.css',
+                'styles/typing_notifications.css',
                 # We don't want fonts.css on QtWebKit, so its omitted here
             ),
             'output_filename': 'min/app-fontcompat.css'
@@ -729,6 +730,7 @@ PIPELINE = {
                 'styles/thirdparty-fonts.css',
                 'styles/fonts.css',
                 'styles/media.css',
+                'styles/typing_notifications.css',
             ),
             'output_filename': 'min/app.css'
         },
@@ -888,6 +890,7 @@ JS_SPECS = {
             'js/custom_markdown.js',
             'js/bot_data.js',
             'js/reactions.js',
+            'js/typing.js',
             # JS bundled by webpack is also included here if PIPELINE_ENABLED setting is true
         ],
         'output_filename': 'min/app.js'