diff --git a/app/assets/javascripts/discourse/components/small-action.js.es6 b/app/assets/javascripts/discourse/components/small-action.js.es6
index b66024987eb..8a17c41031c 100644
--- a/app/assets/javascripts/discourse/components/small-action.js.es6
+++ b/app/assets/javascripts/discourse/components/small-action.js.es6
@@ -3,7 +3,15 @@ import { autoUpdatingRelativeAge } from 'discourse/lib/formatter';
 export function actionDescriptionHtml(actionCode, createdAt, username) {
   const dt = new Date(createdAt);
   const when = autoUpdatingRelativeAge(dt, { format: 'medium-with-ago' });
-  const who = username ? `<a class="mention" href="/users/${username}">@${username}</a>` : "";
+
+  var who = "";
+  if (username) {
+    if (actionCode === "invited_group" || actionCode === "removed_group") {
+      who = `<a class="mention-group" href="/groups/${username}">@${username}</a>`;
+    } else {
+      who = `<a class="mention" href="/users/${username}">@${username}</a>`;
+    }
+  }
   return I18n.t(`action_codes.${actionCode}`, { who, when }).htmlSafe();
 }
 
diff --git a/app/assets/javascripts/discourse/components/user-selector.js.es6 b/app/assets/javascripts/discourse/components/user-selector.js.es6
index aa1c4b7e81c..ab695e8b2b0 100644
--- a/app/assets/javascripts/discourse/components/user-selector.js.es6
+++ b/app/assets/javascripts/discourse/components/user-selector.js.es6
@@ -13,10 +13,13 @@ export default TextField.extend({
         allowedUsers = this.get('allowedUsers') === 'true';
 
     function excludedUsernames() {
+      // hack works around some issues with allowAny eventing
+      const usernames = self.get('single') ? [] : selected;
+
       if (currentUser && self.get('excludeCurrentUser')) {
-        return selected.concat([currentUser.get('username')]);
+        return usernames.concat([currentUser.get('username')]);
       }
-      return selected;
+      return usernames;
     }
 
     this.$().val(this.get('usernames')).autocomplete({
diff --git a/app/assets/javascripts/discourse/controllers/invite.js.es6 b/app/assets/javascripts/discourse/controllers/invite.js.es6
index c00311a9f9f..6747f1449c3 100644
--- a/app/assets/javascripts/discourse/controllers/invite.js.es6
+++ b/app/assets/javascripts/discourse/controllers/invite.js.es6
@@ -121,6 +121,8 @@ export default Ember.Controller.extend(ModalFunctionality, {
   successMessage: function() {
     if (this.get('model.inviteLink')) {
       return I18n.t('user.invited.generated_link_message', {inviteLink: this.get('model.inviteLink'), invitedEmail: this.get('emailOrUsername')});
+    } else if (this.get('hasGroups')) {
+      return I18n.t('topic.invite_private.success_group');
     } else if (this.get('isMessage')) {
       return I18n.t('topic.invite_private.success');
     } else if ( Discourse.Utilities.emailValid(this.get('emailOrUsername')) ) {
@@ -171,7 +173,23 @@ export default Ember.Controller.extend(ModalFunctionality, {
 
       model.setProperties({ saving: true, error: false });
 
-      return this.get('model').createInvite(this.get('emailOrUsername').trim(), groupNames, this.get('customMessage')).then(result => {
+      const onerror = function(e) {
+        if (e.jqXHR.responseJSON && e.jqXHR.responseJSON.errors) {
+          self.set("errorMessage", e.jqXHR.responseJSON.errors[0]);
+        } else {
+          self.set("errorMessage", self.get('isMessage') ? I18n.t('topic.invite_private.error') : I18n.t('topic.invite_reply.error'));
+        }
+        model.setProperties({ saving: false, error: true });
+      };
+
+      if (this.get('hasGroups')) {
+        return this.get('model').createGroupInvite(this.get('emailOrUsername').trim()).then(result => {
+          model.setProperties({ saving: false, finished: true });
+        }).catch(onerror);
+
+      } else {
+
+        return this.get('model').createInvite(this.get('emailOrUsername').trim(), groupNames, this.get('customMessage')).then(result => {
               model.setProperties({ saving: false, finished: true });
               if (!this.get('invitingToTopic')) {
                 Invite.findInvitedBy(this.currentUser, userInvitedController.get('filter')).then(invite_model => {
@@ -181,14 +199,8 @@ export default Ember.Controller.extend(ModalFunctionality, {
               } else if (this.get('isMessage') && result && result.user) {
                 this.get('model.details.allowed_users').pushObject(Ember.Object.create(result.user));
               }
-            }).catch(function(e) {
-              if (e.jqXHR.responseJSON && e.jqXHR.responseJSON.errors) {
-                self.set("errorMessage", e.jqXHR.responseJSON.errors[0]);
-              } else {
-                self.set("errorMessage", self.get('isMessage') ? I18n.t('topic.invite_private.error') : I18n.t('topic.invite_reply.error'));
-              }
-              model.setProperties({ saving: false, error: true });
-            });
+            }).catch(onerror);
+      }
     },
 
     generateInvitelink() {
diff --git a/app/assets/javascripts/discourse/controllers/topic.js.es6 b/app/assets/javascripts/discourse/controllers/topic.js.es6
index 2c6d56a021f..0062c13bda5 100644
--- a/app/assets/javascripts/discourse/controllers/topic.js.es6
+++ b/app/assets/javascripts/discourse/controllers/topic.js.es6
@@ -256,6 +256,10 @@ export default Ember.Controller.extend(SelectedPostsCount, BufferedContent, {
       return this.get('model.details').removeAllowedUser(user);
     },
 
+    removeAllowedGroup(group) {
+      return this.get('model.details').removeAllowedGroup(group);
+    },
+
     deleteTopic() {
       this.deleteTopic();
     },
diff --git a/app/assets/javascripts/discourse/models/topic-details.js.es6 b/app/assets/javascripts/discourse/models/topic-details.js.es6
index 3be04f6ec31..833af1e1988 100644
--- a/app/assets/javascripts/discourse/models/topic-details.js.es6
+++ b/app/assets/javascripts/discourse/models/topic-details.js.es6
@@ -63,6 +63,18 @@ const TopicDetails = RestModel.extend({
     });
   },
 
+  removeAllowedGroup(group) {
+    const groups = this.get('allowed_groups');
+    const name = group.name;
+
+    return Discourse.ajax("/t/" + this.get('topic.id') + "/remove-allowed-group", {
+      type: 'PUT',
+      data: { name: name }
+    }).then(() => {
+      groups.removeObject(groups.findProperty('name', name));
+    });
+  },
+
   removeAllowedUser(user) {
     const users = this.get('allowed_users');
     const username = user.get('username');
diff --git a/app/assets/javascripts/discourse/models/topic.js.es6 b/app/assets/javascripts/discourse/models/topic.js.es6
index 8e8fd7c8ef4..53cf24f2a8a 100644
--- a/app/assets/javascripts/discourse/models/topic.js.es6
+++ b/app/assets/javascripts/discourse/models/topic.js.es6
@@ -309,6 +309,13 @@ const Topic = RestModel.extend({
     });
   },
 
+  createGroupInvite(group) {
+    return Discourse.ajax("/t/" + this.get('id') + "/invite-group", {
+      type: 'POST',
+      data: { group }
+    });
+  },
+
   createInvite(user, group_names, custom_message) {
     return Discourse.ajax("/t/" + this.get('id') + "/invite", {
       type: 'POST',
diff --git a/app/assets/javascripts/discourse/templates/modal/invite.hbs b/app/assets/javascripts/discourse/templates/modal/invite.hbs
index 98b1eb7890d..e7215807c08 100644
--- a/app/assets/javascripts/discourse/templates/modal/invite.hbs
+++ b/app/assets/javascripts/discourse/templates/modal/invite.hbs
@@ -11,9 +11,22 @@
     <label>{{inviteInstructions}}</label>
     {{#if allowExistingMembers}}
       {{#if isPrivateTopic}}
-        {{user-selector single="true" allowAny=true excludeCurrentUser="true" usernames=emailOrUsername allowedUsers="true" topicId=topicId placeholderKey=placeholderKey}}
+        {{user-selector single="true"
+                        allowAny=true
+                        excludeCurrentUser="true"
+                        usernames=emailOrUsername
+                        allowedUsers="true"
+                        topicId=topicId
+                        placeholderKey=placeholderKey}}
       {{else}}
-        {{user-selector single="true" allowAny=true excludeCurrentUser="true" usernames=emailOrUsername placeholderKey=placeholderKey}}
+        {{user-selector
+            single="true"
+            allowAny=true
+            excludeCurrentUser="true"
+            includeMentionableGroups="true"
+            hasGroups=hasGroups
+            usernames=emailOrUsername
+            placeholderKey=placeholderKey}}
       {{/if}}
     {{else}}
       {{text-field value=emailOrUsername placeholderKey="topic.invite_reply.email_placeholder"}}
diff --git a/app/assets/javascripts/discourse/templates/topic.hbs b/app/assets/javascripts/discourse/templates/topic.hbs
index a173827ec85..086fc13642f 100644
--- a/app/assets/javascripts/discourse/templates/topic.hbs
+++ b/app/assets/javascripts/discourse/templates/topic.hbs
@@ -113,6 +113,7 @@
               toggleWiki="toggleWiki"
               toggleSummary="toggleSummary"
               removeAllowedUser="removeAllowedUser"
+              removeAllowedGroup="removeAllowedGroup"
               showInvite="showInvite"
               topVisibleChanged="topVisibleChanged"
               currentPostChanged="currentPostChanged"
diff --git a/app/assets/javascripts/discourse/widgets/post-small-action.js.es6 b/app/assets/javascripts/discourse/widgets/post-small-action.js.es6
index 4f56c01ddb5..882cbc9746b 100644
--- a/app/assets/javascripts/discourse/widgets/post-small-action.js.es6
+++ b/app/assets/javascripts/discourse/widgets/post-small-action.js.es6
@@ -20,7 +20,9 @@ const icons = {
   'visible.disabled': 'eye-slash',
   'split_topic': 'sign-out',
   'invited_user': 'plus-circle',
+  'invited_group': 'plus-circle',
   'removed_user': 'minus-circle',
+  'removed_group': 'minus-circle',
   'public_topic': 'comment',
   'private_topic': 'envelope'
 };
diff --git a/app/assets/javascripts/discourse/widgets/private-message-map.js.es6 b/app/assets/javascripts/discourse/widgets/private-message-map.js.es6
index 7d19c8ed4e1..7d311b70b3a 100644
--- a/app/assets/javascripts/discourse/widgets/private-message-map.js.es6
+++ b/app/assets/javascripts/discourse/widgets/private-message-map.js.es6
@@ -3,12 +3,33 @@ import { createWidget } from 'discourse/widgets/widget';
 import { h } from 'virtual-dom';
 import { avatarFor } from 'discourse/widgets/post';
 
+createWidget('pm-remove-group-link', {
+  tagName: 'a.remove-invited',
+
+  html() {
+    return iconNode('times');
+  },
+
+  click() {
+    bootbox.confirm(I18n.t("private_message_info.remove_allowed_group", {name: this.attrs.name}), (confirmed) => {
+      if (confirmed) { this.sendWidgetAction('removeAllowedGroup', this.attrs); }
+    });
+  }
+});
+
 createWidget('pm-map-user-group', {
   tagName: 'div.user.group',
 
   html(attrs) {
-    const link = h('a', { attributes: { href: Discourse.getURL(`/groups/${attrs.name}`) } }, attrs.name);
-    return [iconNode('users'), ' ', link];
+    const link = h('a', { attributes: { href: Discourse.getURL(`/groups/${attrs.group.name}`) } }, attrs.group.name);
+    const result = [iconNode('users'), ' ', link];
+
+    if (attrs.canRemoveAllowedUsers) {
+      result.push(' ');
+      result.push(this.attach('pm-remove-group-link', attrs.group));
+    }
+
+    return result;
   }
 });
 
@@ -51,12 +72,12 @@ export default createWidget('private-message-map', {
     const participants = [];
 
     if (attrs.allowedGroups.length) {
-      participants.push(attrs.allowedGroups.map(ag => this.attach('pm-map-user-group', ag)));
+      participants.push(attrs.allowedGroups.map(ag => this.attach('pm-map-user-group', {group: ag, canRemoveAllowedUsers: attrs.canRemoveAllowedUsers})));
     }
 
     if (attrs.allowedUsers.length) {
-      participants.push(attrs.allowedUsers.map(ag => {
-        return this.attach('pm-map-user', { user: ag, canRemoveAllowedUsers: attrs.canRemoveAllowedUsers });
+      participants.push(attrs.allowedUsers.map(au => {
+        return this.attach('pm-map-user', { user: au, canRemoveAllowedUsers: attrs.canRemoveAllowedUsers });
       }));
     }
 
diff --git a/app/controllers/topics_controller.rb b/app/controllers/topics_controller.rb
index 3ffc9a86a56..24f7626e3e2 100644
--- a/app/controllers/topics_controller.rb
+++ b/app/controllers/topics_controller.rb
@@ -375,6 +375,34 @@ class TopicsController < ApplicationController
     end
   end
 
+  def remove_allowed_group
+    params.require(:name)
+    topic = Topic.find_by(id: params[:topic_id])
+    guardian.ensure_can_remove_allowed_users!(topic)
+
+    if topic.remove_allowed_group(current_user, params[:name])
+      render json: success_json
+    else
+      render json: failed_json, status: 422
+    end
+  end
+
+  def invite_group
+    group = Group.find_by(name: params[:group])
+    raise Discourse::NotFound unless group
+
+    topic = Topic.find_by(id: params[:topic_id])
+
+    if topic.private_message?
+      guardian.ensure_can_send_private_message!(group)
+      topic.invite_group(current_user, group)
+
+      render json: success_json
+    else
+      render json: failed_json, status: 422
+    end
+  end
+
   def invite
     username_or_email = params[:user] ? fetch_username : fetch_email
 
diff --git a/app/models/topic.rb b/app/models/topic.rb
index 77f2e0afd75..e793f7c7422 100644
--- a/app/models/topic.rb
+++ b/app/models/topic.rb
@@ -577,6 +577,19 @@ class Topic < ActiveRecord::Base
     changed_to_category(cat)
   end
 
+  def remove_allowed_group(removed_by, name)
+    if group = Group.find_by(name: name)
+      group_user = topic_allowed_groups.find_by(group_id: group.id)
+      if group_user
+        group_user.destroy
+        add_small_action(removed_by, "removed_group", group.name)
+        return true
+      end
+    end
+
+    false
+  end
+
   def remove_allowed_user(removed_by, username)
     if user = User.find_by(username: username)
       topic_user = topic_allowed_users.find_by(user_id: user.id)
@@ -590,6 +603,19 @@ class Topic < ActiveRecord::Base
     false
   end
 
+  def invite_group(user, group)
+    TopicAllowedGroup.create!(topic_id: id, group_id: group.id)
+
+    last_post = posts.order('post_number desc').where('not hidden AND posts.deleted_at IS NULL').first
+    if last_post
+      # ensure all the notifications are out
+      PostAlerter.new.after_save_post(last_post)
+      add_small_action(user, "invited_group", group.name)
+    end
+
+    true
+  end
+
   # Invite a user to the topic by username or email. Returns success/failure
   def invite(invited_by, username_or_email, group_ids=nil, custom_message=nil)
     if private_message?
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index e53038c639a..3d142ef2c0e 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -144,7 +144,9 @@ en:
       private_topic: "made this topic private %{when}"
       split_topic: "split this topic %{when}"
       invited_user: "invited %{who} %{when}"
+      invited_group: "invited %{who} %{when}"
       removed_user: "removed %{who} %{when}"
+      removed_group: "removed %{who} %{when}"
       autoclosed:
         enabled: 'closed %{when}'
         disabled: 'opened %{when}'
@@ -908,6 +910,7 @@ en:
       title: "Message"
       invite: "Invite Others..."
       remove_allowed_user: "Do you really want to remove {{name}} from this message?"
+      remove_allowed_group: "Do you really want to remove {{name}} from this message?"
 
     email: 'Email'
     username: 'Username'
@@ -1448,6 +1451,7 @@ en:
         email_or_username_placeholder: "email address or username"
         action: "Invite"
         success: "We've invited that user to participate in this message."
+        success_group: "We've invited that group to participate in this message."
         error: "Sorry, there was an error inviting that user."
         group_name: "group name"
 
diff --git a/config/routes.rb b/config/routes.rb
index 10694913693..ee654ac8a64 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -547,6 +547,7 @@ Discourse::Application.routes.draw do
   put "t/:topic_id/make-banner" => "topics#make_banner", constraints: {topic_id: /\d+/}
   put "t/:topic_id/remove-banner" => "topics#remove_banner", constraints: {topic_id: /\d+/}
   put "t/:topic_id/remove-allowed-user" => "topics#remove_allowed_user", constraints: {topic_id: /\d+/}
+  put "t/:topic_id/remove-allowed-group" => "topics#remove_allowed_group", constraints: {topic_id: /\d+/}
   put "t/:topic_id/recover" => "topics#recover", constraints: {topic_id: /\d+/}
   get "t/:topic_id/:post_number" => "topics#show", constraints: {topic_id: /\d+/, post_number: /\d+/}
   get "t/:topic_id/last" => "topics#show", post_number: 99999999, constraints: {topic_id: /\d+/}
@@ -557,6 +558,7 @@ Discourse::Application.routes.draw do
   get "t/:topic_id/posts" => "topics#posts", constraints: {topic_id: /\d+/}, format: :json
   post "t/:topic_id/timings" => "topics#timings", constraints: {topic_id: /\d+/}
   post "t/:topic_id/invite" => "topics#invite", constraints: {topic_id: /\d+/}
+  post "t/:topic_id/invite-group" => "topics#invite_group", constraints: {topic_id: /\d+/}
   post "t/:topic_id/move-posts" => "topics#move_posts", constraints: {topic_id: /\d+/}
   post "t/:topic_id/merge-topic" => "topics#merge_topic", constraints: {topic_id: /\d+/}
   post "t/:topic_id/change-owner" => "topics#change_post_owners", constraints: {topic_id: /\d+/}
diff --git a/spec/controllers/topics_controller_spec.rb b/spec/controllers/topics_controller_spec.rb
index e66a8085c5e..ecfd606346e 100644
--- a/spec/controllers/topics_controller_spec.rb
+++ b/spec/controllers/topics_controller_spec.rb
@@ -950,6 +950,35 @@ describe TopicsController do
     end
   end
 
+  describe 'invite_group' do
+    let :admins do
+      Group[:admins]
+    end
+
+    let! :admin do
+      log_in :admin
+    end
+
+    before do
+      admins.alias_level = Group::ALIAS_LEVELS[:everyone]
+      admins.save!
+    end
+
+    it "disallows inviting a group to a topic" do
+      topic = Fabricate(:topic)
+      xhr :post, :invite_group, topic_id: topic.id, group: 'admins'
+      expect(response.status).to eq(422)
+    end
+
+    it "allows inviting a group to a PM" do
+      topic = Fabricate(:private_message_topic)
+      xhr :post, :invite_group, topic_id: topic.id, group: 'admins'
+
+      expect(response.status).to eq(200)
+      expect(topic.allowed_groups.first.id).to eq(admins.id)
+    end
+  end
+
   describe 'invite' do
 
     describe "group invites" do
diff --git a/spec/models/topic_spec.rb b/spec/models/topic_spec.rb
index e1f48980ffd..75fc7beb581 100644
--- a/spec/models/topic_spec.rb
+++ b/spec/models/topic_spec.rb
@@ -372,6 +372,25 @@ describe Topic do
       context 'existing user' do
         let(:walter) { Fabricate(:walter_white) }
 
+        context 'by group name' do
+
+          it 'can add admin to allowed groups' do
+            admins = Group[:admins]
+            admins.alias_level = Group::ALIAS_LEVELS[:everyone]
+            admins.save
+
+            expect(topic.invite_group(topic.user, admins)).to eq(true)
+
+            expect(topic.allowed_groups.include?(admins)).to eq(true)
+
+            expect(topic.remove_allowed_group(topic.user, 'admins')).to eq(true)
+            topic.reload
+
+            expect(topic.allowed_groups.include?(admins)).to eq(false)
+          end
+
+        end
+
         context 'by username' do
 
           it 'adds and removes walter to the allowed users' do