A video session manager and method for enabling, optimizing and managing inter-domain video calling, telepresence and videoconferencing sessions, in exclusive video sessions, or within multi-modal communications sessions. The video session manager and method is operative for receiving and analyzing a communications session request from one or more endpoints (users); determining the viability of a communication session based on one or more attributes of the session; connecting the one or more requesting endpoints to start the session; continuously or periodically monitoring the session for problems with or changes in the session; and altering the parameters of the session in accordance with one or more predetermined policies, if a problem or change is detected, in order to maintain the viability of the session.