A communication management system manages session information regarding a contents data session being established to communicate contents data among a plurality of participating communication terminals, and receives a request for registering a group of the plurality of participating communication terminals that are currently participating in the session, from a first participating communication terminal of the plurality of participating communication terminals, during when the session is being established. In response to the request for registering, the communication management system stores first candidate information of the first participating communication terminal in a first memory, the first candidate information associating the group of the plurality of participating communication terminals with the first participating communication terminal.