PrOMIS assumes that the evaluation research process is a collaboration of researchers, programs, Department of Human Services, and family court. It views evaluation as a continuous process rather than one or more discrete studies. At all stages, the utility of the data collected and the information produced is of paramount importance. PrOMIS collects data at three points in time: intake, comprising the time from court disposition to intake to the program; discharge, the point at which the juvenile ends the program; and follow-up, 6 months after discharge. At the intake stage PrOMIS uses program staff assessment and self-report measures. At discharge, the staff and self-report measures are repeated, providing a set of pre-post outcome measures that can be used to evaluate program goals. The discharge data stage also incorporates a detailed set of measures on the type of services provided during the intervention. Follow-up includes a check of court records for any new petitions and, when possible, an interview with the juvenile and a parent/guardian. Since PrOMIS became operational in June 1996, it has compiled data on more than 3,000 prevention cases. This report shows that prevention programs in Philadelphia are working to develop policies that use relevant information. As this study shows, PrOMIS provides the outcome information necessary for prevention programs to identify effective prevention approaches and to help transfer this knowledge within the field. 1 figure, 1 table, and 6 references