This sourcebook, which builds on a 1993 publication, "The Prevention of Youth Violence: A Framework for Community Action," offers insight into best practices to prevent violence by children and adolescents. It was developed with input from people working to prevent youth violence and people whose positions made them likely to play a role in violence prevention efforts. Researchers interviewed teachers, school administrators, members of community-based organizations, employees and volunteers at social service agencies, health department personnel, program planners and practitioners, and researchers from universities across the United States regarding what they would like to see in a sourcebook. They also conducted an extensive literature review on youth violence prevention. Chapter 1 reviews general principals of intervention planning, implementation, and evaluation. Chapter 2 builds on the experiences of others who have worked to prevent violence by children and adolescents, discussing the best practices of four key youth prevention strategies (parent- and family-based, home-visiting, social-cognitive, and mentoring strategies). This chapter also includes resources for more information about programs using these practices. Two appendixes offer a youth violence fact sheet and a public health approach. (Chapters contain references.) (SM)