Drawing on many years of experience in the barrios as a youth worker, high school teacher, and researcher, Vigil 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 actual gang members, he reveals how the gang often functions as parent, school, and law enforcement in the absence of other role models in the gang members' lives. And he accounts for the longevity of gangs, sometimes over decades, by showing how they offer barrio youth a sense of identity and belonging nowhere else available.