In 1972, Main Township (Illinois) High School District 207 eliminated its inhouse data processing operation and joined Educational Management Systems (EMS), a regional data processing cooperative. EMS was created by the Institute for Educational Research (IER), which first conducted a thorough study of school district's data processing practices. The IER study indicated that the only feasible way for districts to significantly improve the cost-effectiveness of their data processing operations was to seek the economy of size, the effectiveness of integrated file structures, and the efficiency of cooperative effort. By establishing a regional computer utility, member school districts are able to share the cost required to obtain and maintain the necessary computer staff. Each district can use the computer to satisfy its own requirements independently of other districts using the system. Joining EMS has helped the Maine Township district meet its administrative and instructional data processing needs more completely and economically than before. In fact, most EMS member districts have enjoyed substantial cost savings and a rather dramatic increase in service since joining the cooperative. (Author/JG)