diff --git a/web/channels/system_channel.ex b/web/channels/system_channel.ex
--- a/web/channels/system_channel.ex
+++ b/web/channels/system_channel.ex
@@ -3,36 +3,59 @@
 
   alias KolabChat.Presence
 
-  def join("system", _, socket) do
-    Process.flag(:trap_exit, true)
-    :timer.send_interval(10000, :ping)
+  @status [
+    # user is available for chat
+    :online,
+    :away,
+    # user is connected and visible, but not available
+    :busy,
+    :unavailable,
+    # user is shown as offline
+    :invisible,
+    :offline
+  ]
+
+  def join("system", %{"context" => context}, socket) do
+    socket = assign(socket, :context, context)
     send self(), :after_join
 
     {:ok, socket}
   end
 
   def handle_info(:after_join, socket) do
+    push socket, "presence_state", Presence.list(socket)
+    push socket, "info", %{user: socket.assigns.user.username}
+
     Presence.track(socket, socket.assigns.user.username, %{
-      status: "online"
+      status: :online,
+      context: socket.assigns.context
     })
 
-    push socket, "info", %{user: socket.assigns.user.username}
-    push socket, "presence_state", Presence.list(socket)
-
     {:noreply, socket}
   end
 
-  def handle_info(:ping, socket) do
-    push socket, "new:msg", %{user: "SYSTEM", body: "ping"}
-
+  def handle_in("set-status", %{"status" => status}, socket) do
+    update_presence_status(check_status(status), socket)
     {:noreply, socket}
   end
 
-  def handle_in("set-status", %{"status" => status}, socket) do
+  defp update_presence_status(:invalid, _socket), do: :ok
+  defp update_presence_status(status, socket) do
     {:ok, _} = Presence.update(socket, socket.assigns.user.username, %{
-      status: status
+      status: status,
+      context: socket.assigns.context
     })
+  end
 
-    {:noreply, socket}
+  # Makes sure the provided status name is supported
+  # Returns status name as an atom
+  defp check_status(status) do
+    status = String.to_atom(status)
+
+    if Enum.member?(@status, status) do
+      status
+    else
+      :invalid
+    end
   end
 end
diff --git a/web/static/css/widgets.css b/web/static/css/widgets.css
--- a/web/static/css/widgets.css
+++ b/web/static/css/widgets.css
@@ -1,15 +1,18 @@
 /* Style for chat application widgets */
 
-.status-online .glyphicon-user {
+.status-online .glyphicon-user,
+.status-away .glyphicon-user {
   color: green;
 }
 
-.status-away .glyphicon-user {
-  color: grey;
+.status-busy .glyphicon-user,
+.status-unavailable .glyphicon-user {
+  color: red;
 }
 
-.status-busy .glyphicon-user {
-  color: red;
+.status-invisible .glyphicon-user,
+.status-offline .glyphicon-user {
+  color: gray;
 }
 
 .userlist .btn-group {
diff --git a/web/static/js/api.js b/web/static/js/api.js
--- a/web/static/js/api.js
+++ b/web/static/js/api.js
@@ -10,6 +10,7 @@
   /**
    * Configuration parameters:
    *   - token: User session token
+   *   - context: KolabChat instance identifier
    *   - roomId: Chat room Id to join in
    *   - userListElement: Id of HTML element where to put userslist widget
    *   - userStatusElement: Id of HTML element where to put users status widget
@@ -19,6 +20,9 @@
   constructor(config)
   {
     this.config = config || {}
+
+    if (!this.config.context)
+      this.config.context = location.hostname;
   }
 
   /**
@@ -34,7 +38,7 @@
     // TODO: for integration with external systems we'll use configurable full wss:// url
 
     this.socket = new Socket("/socket", {
-      params: {token: this.config.token},
+      params: {token: this.config.token, context: this.config.context},
       logger: ((kind, msg, data) => { console.log(`${kind}: ${msg}`, data) }),
     })
 
@@ -91,7 +95,7 @@
    */
   initPresence()
   {
-    this.system = this.socket.channel("system")
+    this.system = this.socket.channel("system", {context: this.config.context})
 
     this.system.on("info", info => {
       this.username = info.user
@@ -146,7 +150,7 @@
     let userPresence
 
     if (this.userStatusWidget && (userPresence = presences[this.username])) {
-      userPresence = this.listBy(this.username, userPresence)
+      userPresence = this.listBy(this.username, userPresence, this.config.context)
       this.userStatusWidget.render(userPresence)
     }
 
@@ -156,11 +160,27 @@
     }
   }
 
-  listBy(user, {metas: metas})
+  listBy(user, {metas: metas}, context)
   {
+    let statusWeights = {
+      offline: 0,
+      busy: 10,
+      away: 20,
+      online: 30
+    }
+
+    // Find "best" availability status for the user
+    // If set, narrow the result to the current session context
+    let mostAvailableStatus = metas.reduce((best, meta) => {
+        if (context && context != meta.context)
+          return best
+        return statusWeights[best] > statusWeights[meta.status] ? best : meta.status
+      },
+      "offline")
+
     return {
       user: user,
-      status: metas[0].status
+      status: mostAvailableStatus
     }
   }
 
diff --git a/web/static/js/widgets/userstatus.js b/web/static/js/widgets/userstatus.js
--- a/web/static/js/widgets/userstatus.js
+++ b/web/static/js/widgets/userstatus.js
@@ -9,6 +9,19 @@
   {
     this.config = config || {}
     this.id = id
+
+    // FIXME: should we get that list from the backend?
+    this.status_list = [
+      // user is available for chat
+      "online",
+      "away",
+      // user is connected and visible, but not available
+      "busy",
+      "unavailable",
+      // user is shown as offline
+      "invisible",
+      "offline"
+    ];
   }
 
   /**
@@ -18,6 +31,11 @@
   {
     let userStatusElement = document.getElementById(this.id)
     let icon = '<span class="glyphicon glyphicon-user"></span>'
+    let options = list => {
+      return $.map(list, status =>
+          `<li><a href="#" class="status-${status}">${icon} ${status}</a></li>`
+        ).join("\n")
+    }
 
     userStatusElement.innerHTML = `
       <div class="dropdown">
@@ -28,9 +46,7 @@
           <span class="caret"></span>
         </button>
         <ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
-          <li><a href="#" class="status-online">${icon} Online</a></li>
-          <li><a href="#" class="status-away">${icon} Away</a></li>
-          <li><a href="#" class="status-busy">${icon} Busy</a></li>
+        ` + options(this.status_list) + `
         </ul>
       </div>
     `