Abstract: A schedule management server is provided with a transmitting means for transmitting information of the number of necessary staffs estimated in advance to terminal devices for transmitting desirable working schedules. A computer (1) comprises a communication network (3) and a terminal device (4). The computer (1) generates assumed schedule data indicative of schedules assumed for a plurality of staffs and starts receiving desired schedule data indicative of schedules desired by the plurality of staffs from the terminal device (4) connected to the communication network (3). The computer (1) sends the assumed schedule data to the terminal device (4) at the request of the terminal device (4) connected to the communication network (3). The computer (1) receives and stores the desired schedule data indicative of staffs' desired schedules from the terminal device (4) and generates temporarily determined schedules for the staffs based on the assumed schedule data and the desired schedule data.