Individual papers examine problems of definition in criminology generally and how these problems make the areas of gang research more difficult; present results of a self-report survey of juvenile gang involvement; and summarize the results of a survey of 79 large metropolitan police agencies regarding the nature and extent of gang activity. Additional papers present theories associated with the study of gangs and gang activity and the gender, racial, and ethnic characteristics of gangs. Further papers present results of empirical studies of gangs, drugs, and juvenile delinquency; differences between gang and nongang homicides; routine activities and a subculture of violence; the involvement of women in outlaw motorcycle gangs; prison gang members in the Texas correctional system; and Jamaican posses. Other papers focus on gang prevention, intervention, and law enforcement responses, with emphasis on community organization, public policy, police responses, preventive interventions for street gangs, and assessment and clinical interventions with deviant adolescent subcultures. Figures, tables, notes, chapter reference lists, and index