The study concludes that gang activity among Mexican- American youths in Los Angeles has grown and flourished. In the past, community leaders and law enforcement officials have approached the problem without analyzing the reasons for and the attraction of gangs in the barrios. They have tried to eliminate the gangs without addressing the reasons for their existence and persistence. Rejecting this approach, the author asserts that only by understanding the complex factors that spawn and maintain gangs can gang violence be eliminated. Drawing on many years of experience in the barrios as a youth worker, high school teacher, and researcher, the author identifies the elements from which gangs spring: isolation from the dominant culture, poverty, family stress and crowded households, peer pressure, and the adolescent struggle for self-identity. Using interviews with gang members, the study shows how gangs often function as parent, school, and law enforcement in the absence of other role models in the gang members' lives. The author accounts for the longevity of gangs, sometimes over decades, by showing how they offer barrio youth a sense of identity and belonging not available to them elsewhere. 240 references and a subject index