Most evidence-based prevention and treatment interventions are not routinely implemented with college students, who represent a large group of young adults at high risk for mental health problems. This project, which evaluated 3 approaches of implementation support for peer leaders who delivered a prevention program with a particularly strong evidence-base compared to changes observed in outcomes in response to usual care at the universities before implementation, advanced knowledge of this innovative and economical way to provide college prevention programs to reduce the burden of mental illness in this population.