The five sites were selected based on the severity of their drug and gang problems and for regional diversity, ethnic diversity in gangs, and variations in their approaches to gang problems. Data were originally collected in 1991-92 by means of site visits that included structured interviews. A 1996 follow-up study used telephone interviews and document reviews to gather additional data on how the agency's approach had changed over the last 5 years. The analysis revealed that the manifestation of gang problems varied significantly among the cities studied. In 1991, most of the police agencies used a combination of prevention, suppression, intelligence-gathering, and investigation strategies. Between 1991 and 1996 the two major trends in police responses were increased efforts at interorganizational collaboration and improved systems for information management and information sharing. Other common themes were the broadening responses of specialized gang units, similar approaches to responding to the media, and efforts to strengthen ties with community organizations to address gang problems. Chapter reference notes