Abstract: The invention is intended to co-ordinate telecommunication services (2) provided to users by means of terminals (3, 4, 5) which are connected to different telecommunication networks (1). For said purpose, the invention comprises the following steps: a service mediation server (10) co-ordinates different telecommunication services activated by users; the terminals (3, 4, 5) connect to the server and transmit users profiles thereto, said profiles specifying availability modes, activate the profiles and availability modes and access the connected services; and the service mediation server determines a reachability state for each user, which is dependent on at least one user terminal being connected to the server and the active availability mode and profile of the user, and transmits said state to the connected user terminals specified in a list of contacts in the active profile of the user.