A system to adaptively control multimedia communication sessions includes a mediator unit in an intermediary communication position between two or more remote clients and a media infrastructure. The mediator unit includes a receiver, a transmitter and a control processor that controls the receiver and the transmitter. The mediator unit communicates remote clients across a communication network, where the first client initiates a communication session and the mediator unit assigns a unique session identifier to the communication message. Additional remote clients send join requests including the unique session identifier, and the mediator unit acts as a back-to-back user agent to pass messages between two remote clients of a two-client communication session. The control processor configured to execute predefined context-sensitive strategies including the number of remote clients in the communication session, bridging incompatible peer-to-peer communications, supporting multiple devices of a single remote client, and dynamic allocation of multipoint control unit resources.