At one time, youth gangs had a mainly social basis for their organization and existence. However, they are now motivated by violence, extortion, intimidation, and the illegal trafficking of drugs and weapons. To address the problem, school administrators should establish clear behavior guidelines that specifically prohibit gang activity and that encourage responsible citizenship. Prompt graffiti removal and provision of adequate support and protection for victims are also crucial. Using parent volunteers to provide added supervision in the school and community and teaching parents to become good role models are also important strategies. Law enforcement strategies include establishing a visible patrol, developing accurate gang intelligence, following up on rumors, cooperating with schools, and keeping informed about the latest national information. Important prosecution, probation, and parole strategies include vertical prosecution, witness protection plans, information networks, record sharing, enhanced supervision and counseling, and increased surveillance. Photograph.