A communication control apparatus comprises a terminal control part that generates available-terminal information representing a communication terminal belonging to a group of available-terminals and also generates call-status information representing one of the communication terminals having calls and also representing the media of the communication terminals; a terminal/media selecting part that, upon detection of an event occurrence, if the call-status information matches terminal/media information of a terminal/media information storing part and further if changed-terminal/media information of the terminal/media information storing part is included in the available-terminal information, then determines the communication terminal represented by the changed-terminal/media information as a communication terminal to be incorporated into the calls of the media of the communication terminals; and a session control part that establishes a call of the medium of the determined communication terminal between the determined communication terminal and a communication terminal of another user.