Psychologists began their formal involvement with police agencies in the 1960's. A recent survey of police psychology in 50 of the country's largest police agencies corroborated the continued growth of policy psychology and demonstrated that a broadened role has been institutionalized in many agencies. The survey also revealed that coordination of psychological services in police agencies and credibility of psychological services are persistent problems. The 65 police psychologists who responded characterized officers involved in excessive force in five categories: chronic offenders, police with multiple and unresolved job-related traumas, immature officers who display early problems with use of force, heavy-handed veterans who believe that good police work involves the use of force, and police officers whose personal problems become overwhelming. Both prevention and intervention are important strategies for managing police brutality. Preventive activities include preemployment screening. Psychologists also recommend training programs and behavior monitoring systems to detect early warnings of patrol problems. One recommended intervention is the use of debriefing for all police personnel involved in on-duty traumatic incidents. Sixty-two percent of the police psychologists surveyed recommended training as the preferable approach for reducing excessive force, compared to 13 percent who recommended fitness evaluations. Further research is needed for full understanding of the steps needed to control police brutality. Tables and 43 references