While extensive research exists, the field lacks a current and translational synthesis of what works to reduce youth group and gun violence. In response, the Urban Institute developed a research-based practice guide to inform local government, law enforcement, and community-violence-intervention stakeholders as they implement new antiviolence interventions and refine existing ones. This fact sheet summarizes practice guide recommendations around nine practice areas related to building an infrastructure to support a multi-faceted antiviolence strategy and implementing effective violence reduction programs. The recommendations are based on findings from a literature synthesis and scan of relevant antiviolence practice.