The project used an 88-officer unit, which was later reduced to 60 officers, to conduct its activities. The officers were organized into seven-member squads, which used informal selection procedures to target criminally active targets. The Police Foundation, in cooperation with the District of Columbia Metropolitan Police Department, conducted a multifaceted evaluation that used three types between January 1983 and December 1984 to assess ROP's effectiveness and costs. The results showed that the ROP unit appeared to have achieved its goals of selecting, arresting, and contributing to the incarceration of repeat offenders. However, costs, legal and ethical issues, and other factors suggest the need for other departments to use caution in interpreting the results or adopting the ROP model of perpetrator-oriented proactive policing. 5 references.