Despite spending $25 billion over 30 years fighting a “war on gangs,” the City of Los Angeles saw gang participation and violence mushroom. In 2007, Los Angeles had more than 700 individual gangs with 40,000 members. In response to the crisis, Constance Rice, Co-Director of the Advancement Project, a public policy change organization focused on civil rights issues, spearheaded the development of a 108-page report providing a framework for how the city should approach gang reduction. This case study tells the story of the development of the report, A Call to Action: A Case for a Comprehensive Solution to LA’s Gang Violence Epidemic, which included input from 47 subject matter experts and prompted the creation of the Gang Reduction and Youth Development (GRYD) office. This collaborative program implements the city’s new comprehensive, community-building approach to gangs where police officers work hand-in-hand with residents to clean up neighborhoods and prevent violence.