The authors designed and evaluated an innovative, branded campaign called 'Adelante' to promote positive youth development (PYD) and reduce risk behaviors among Latino youth near Washington, DC. Repeated cross-sectional surveys were conducted in the intervention and a comparison community to evaluate campaign exposure and changes in PYD outcomes. The sample consisted of 1549 Latino and immigrant adolescents surveyed at three time points in intervention and comparison communities. A social marketing campaign was implemented using outdoor advertising, Web, video and social media channels to promote PYD and health outcomes over a 1-year period from 2015 to 2016. Measures included media use; self-reported exposure to campaign promotions; Adelante message receptivity; validated PYD scales; substance use, sexual risk taking, violence-related knowledge, attitudes, beliefs, intentions and risk behavior. Outcomes were regressed first on campaign exposure to examine dose--response effects of the Adelante campaign over time. Second, we compared outcomes between the Adelante and comparison communities. We observed a positive effect of self-reported exposure on multiple outcomes, including improvements in pro-violence and sexual risk outcomes and lower pro-violence attitudes and lower risky attitudes toward sex. Adelante was effective in improving youth risk outcomes and offers a promising model for future health promotion with Latino and immigrant populations.