Funded by the Centers for Disease Control (grant no. U49CE000773) This project evaluated the impact of established business improvement districts (BIDs) in Los Angeles on community-level factors. Using interviews, a two-wave longitudinal research design, and administrative data the study found significant effects of BIDs on reducing crimes, including aggravated assaults and homicide. Crime displacement appeared minimal. The creation of BIDs appears particularly promising as a solution to urban crime. This study fostered local BID expansion and a larger discussion in the US on engaging the business community in urban areas as part of local health and safety policies.