A PMSS, broadly defined, is an automated data processing system used to improve the efficiency and effectiveness of the prosecutor's office. A model PMSS project, for example, will have an information system that supports prosecution activities, monitors management decisions, and reduces case preparation and processing time. This program brief describes the key steps in developing a system: project management, needs assessment, system planning, system design, coding and testing, implementation and maintenance, and evaluation. System analysts must be brought into the process early to define technically what the prosecutor's office wants and how the analysts will accomplish this. System planning includes an investigation of hardware and software requirements and the development of a project plan. In system design, the functional requirements and data-processing-system specifications are combined to create a model system. In coding and testing, programmers translate the software design into code and continuously test each component until the system functions according to the specifications. System documentation and training should also begin during this phase. Clear management procedures must be in place at the user's site to ensure that the software program and user data are protected. Appendixes provide information on suggested data elements, technical assistance resources, reference material, and the State offices responsible for allocating formula grant funds for the development and acquisition of PMSS projects.