OBJECTIVE: Although early use of alcohol is an immediate and long-term risk for young people, proven prevention strategies are limited. Mass media interventions have been shown to be effective in reducing use of other substances by adolescents. This study tested the impact of a 4-year media campaign designed to reduce alcohol use by early adolescents. METHOD: Theory-based television and radio messages promoting avoidance of alcohol were developed and delivered to an audience of young people as they matured from Grades 4-5 to Grades 7-8. A set of eight school districts was identified as the Media Area; eight matching districts served as the Comparison Area. Independent Grade 7-8 surveys were conducted in all districts at baseline (N= 2897) and after the interventions (N=2419). Unanticipated community coalitions working to reduce youth substance use were introduced into 10 of these 16 communities during the same time period. RESULTS: Exposure of the target audience to the media messages was lower than expected, and the unplanned community coalition interventions may have favored the Comparison Area. The main analyses indicated that the media interventions did not significantly affect alcohol use or its mediators. Supplementary analyses suggested a substantial impact of community coalitions on alcohol use and several key mediators. CONCLUSIONS: The mass media interventions provided by this study had no effect on adolescent alcohol use or its psychosocial mediators. Factors external to the study reduced chances of detecting media effects. Further work is needed to develop and test mass media strategies for alcohol use prevention among early adolescents.