A system controls forwarding of an incoming call. The system receives the incoming call directed to an original recipient. Forwarding settings are processed for routing the incoming call. In some embodiments, the forwarding settings may include a listing of at least one group having more than one member and at least one forwarding instruction based on the at least one group. In these embodiments, the incoming call is forwarded according to the at least one forwarding instruction to at least one first member and at least one second member of the at least one group. The forwarding settings may be based on a user's presence settings, subject to categorization rules, and/or utilize protocol extensions. In some embodiments, the system can map communication routing scenarios to a markup document, such as an XML document, that the system can use to implement team or forwarding call rules. In some embodiments, client devices can set preamble routing independent from the communication server.