Notifying a user of multiple concurrent instant messaging sessions includes receiving a first request to establish a first instant messaging session associated with an instant messaging online identity assigned to a user using a first instant messaging controller and establishing the first instant messaging session in response to the first request. A second request is received to establish a second instant messaging session associated with the instant messaging online identity assigned to the user using a second instant messaging controller that differs from the first instant messaging controller. The second instant messaging session is established in response to the second request. A notification is communicated to at least the first instant messaging controller indicating the establishment of the second instant messaging session.