The primary lessons learned from the four sites involved in the Gang-free School and Communities (GFS) evaluation project fall into seven broad categories: 1) community capacity; 2) role of the project coordinator; 3) location of the grant; 4) parental and community member involvement; 5) range of interventions offered and age span of clients eligible to participate; 6) title of the project; and 7) data collection and analysis issues. Each lesson learned is discussed in further detail. The U.S. Department of Justice, Office of Juvenile Justice and Delinquency Prevention (OJJDP) developed a Comprehensive Gang Model to address developmental issues and risk factors associated with gang violence and crime. The model calls for the demonstration sites to identify and enroll gang-affiliated youth and implement five basic strategies to reduce gang crime and gang membership (community mobilization, social intervention, opportunities provision, suppression, and organizational change and development). The GFS initiative is one of several adaptations of the Model implemented in four sites by OJJDP and the subject of a national impact and process evaluation examination with lessons learned presented in this manuscript. References