Methods, apparatuses and systems facilitating integration of the functionality associated with a first on-line service entity with the functionality associated with a second on-line service entity. Embodiments of the present invention allow a first on-line service entity having its own membership model to efficiently collaborate with a second on-line service entity to offer its users the services of the second on-line service entity in a seamless and consistently branded manner. One implementation obviates the need for synchronization of the membership models between the first and second on-line service entities. One implementation allows the second on-line service entity to provide services to the users associated with the first on-line service entity in a seamless manner without the first on-line service entity having to proxy the session between the second on-line service entity and the users.