Combining focused deterrence, community moral suasion, and social services provision, the Chicago Violence Reduction Strategy (VRS) identified and delivered an antiviolence message to street groups at high risk for both committing and being victims of shootings. VRS was associated with a 23 percent reduction in overall shooting patterns and a 32 percent reduction in shooting victimization for groups treated by VRS, relative to comparison groups matched using a propensity score design. Group members in VRS treatment areas reported improvements in their perceptions of neighborhood safety in surveys, relative to group members in comparison areas. However, high levels of mutual mistrust between law enforcement, community residents, and group members pose a challenge to sustained violence-reduction success.