diff --git a/src/GroupAddressPicker.js b/src/GroupAddressPicker.js
index 2e3c276f65..0b039074f0 100644
--- a/src/GroupAddressPicker.js
+++ b/src/GroupAddressPicker.js
@@ -22,10 +22,20 @@ import MatrixClientPeg from './MatrixClientPeg';
 import GroupStoreCache from './stores/GroupStoreCache';
 
 export function showGroupInviteDialog(groupId) {
+    const description = <div>
+        <div>{ _t("Who would you like to add to this community?") }</div>
+        <div className="warning">
+            { _t(
+                "Warning: any person you add to a community will be publicly "+
+                "visible to anyone who knows the community ID",
+            ) }
+        </div>
+    </div>;
+
     const AddressPickerDialog = sdk.getComponent("dialogs.AddressPickerDialog");
     Modal.createTrackedDialog('Group Invite', '', AddressPickerDialog, {
         title: _t("Invite new community members"),
-        description: _t("Who would you like to add to this community?"),
+        description: description,
         placeholder: _t("Name or matrix ID"),
         button: _t("Invite to Community"),
         validAddressTypes: ['mx-user-id'],
@@ -39,10 +49,20 @@ export function showGroupInviteDialog(groupId) {
 
 export function showGroupAddRoomDialog(groupId) {
     return new Promise((resolve, reject) => {
+        const description = <div>
+            <div>{ _t("Which rooms would you like to add to this community?") }</div>
+            <div className="warning">
+                { _t(
+                    "Warning: any room you add to a community will be publicly "+
+                    "visible to anyone who knows the community ID",
+                ) }
+            </div>
+        </div>;
+
         const AddressPickerDialog = sdk.getComponent("dialogs.AddressPickerDialog");
         Modal.createTrackedDialog('Add Rooms to Group', '', AddressPickerDialog, {
             title: _t("Add rooms to the community"),
-            description: _t("Which rooms would you like to add to this community?"),
+            description: description,
             placeholder: _t("Room name or alias"),
             button: _t("Add to community"),
             pickerType: 'room',
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index b3bbd4eb9a..9fbf16e5da 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -43,18 +43,20 @@
     "%(weekDayName)s %(time)s": "%(weekDayName)s %(time)s",
     "%(weekDayName)s, %(monthName)s %(day)s %(time)s": "%(weekDayName)s, %(monthName)s %(day)s %(time)s",
     "%(weekDayName)s, %(monthName)s %(day)s %(fullYear)s %(time)s": "%(weekDayName)s, %(monthName)s %(day)s %(fullYear)s %(time)s",
-    "Invite new community members": "Invite new community members",
     "Who would you like to add to this community?": "Who would you like to add to this community?",
+    "Warning: any person you add to a community will be publicly visible to anyone who knows the community ID": "Warning: any person you add to a community will be publicly visible to anyone who knows the community ID",
+    "Invite new community members": "Invite new community members",
     "Name or matrix ID": "Name or matrix ID",
     "Invite to Community": "Invite to Community",
-    "Add rooms to the community": "Add rooms to the community",
     "Which rooms would you like to add to this community?": "Which rooms would you like to add to this community?",
+    "Warning: any room you add to a community will be publicly visible to anyone who knows the community ID": "Warning: any room you add to a community will be publicly visible to anyone who knows the community ID",
+    "Add rooms to the community": "Add rooms to the community",
     "Room name or alias": "Room name or alias",
     "Add to community": "Add to community",
     "Failed to invite the following users to %(groupId)s:": "Failed to invite the following users to %(groupId)s:",
     "Invites sent": "Invites sent",
     "Your community invitations have been sent.": "Your community invitations have been sent.",
-    "Failed to invite users community": "Failed to invite users community",
+    "Failed to invite users to community": "Failed to invite users to community",
     "Failed to invite users to %(groupId)s": "Failed to invite users to %(groupId)s",
     "Failed to add the following rooms to %(groupId)s:": "Failed to add the following rooms to %(groupId)s:",
     "Riot does not have permission to send you notifications - please check your browser settings": "Riot does not have permission to send you notifications - please check your browser settings",
@@ -684,7 +686,6 @@
     "Community Member Settings": "Community Member Settings",
     "Publish this community on your profile": "Publish this community on your profile",
     "Long Description (HTML)": "Long Description (HTML)",
-    "Community Name": "Community Name",
     "Description": "Description",
     "Community Settings": "Community Settings",
     "Community %(groupId)s not found": "Community %(groupId)s not found",
@@ -700,7 +701,6 @@
     "Logout": "Logout",
     "You are a member of these communities:": "You are a member of these communities:",
     "Error whilst fetching joined communities": "Error whilst fetching joined communities",
-    "Communities": "Communities",
     "Create a new community": "Create a new community",
     "Create a community to represent your community! Define a set of rooms and your own custom homepage to mark out your space in the Matrix universe.": "Create a community to represent your community! Define a set of rooms and your own custom homepage to mark out your space in the Matrix universe.",
     "Join an existing community": "Join an existing community",