Abstract: A carrier development system wherein registrant communication terminals carried by registrants, an employer end communication terminal, and a system server computer are mutually connected via a communication network such as the Internet, and wherein the computer automatically assigns the registrants, who satisfy employment requirements of an employer end, to time frames (cells) corresponding to job types on each day. A shift creation window, in which the cells are arranged in accordance with cell assignment conditions, is used to automatically assign the registrants to the cells, based on personnel assignment conditions and the preset values of work performance appraisal related to the registrants. The shifts of the respective job types are made open such that they can be viewed via the registrant communication terminals, thereby recruiting for some time interval.