Preventing drinking among youth is a major public health priority. The estimated cost of underage drinking in the U.S. is $61.9 billion annually (Miller, Levy, Spicer, & Taylor, 2006). Alcohol is the most commonly used and abused drug in the U.S., with 41% reporting use in the past 30 days (Johnston, O'Malley, Bachman, & Schulenberg, 2012). Underage persons who drink are likely to drink large amounts (Flewelling, Paschall, & Ringwalt, 2004). Drinking by young people results in as many as 5,000 deaths from motor vehicle crashes, homicides, suicide, and other injuries (Hingson & Kenkel, 2004; National Highway Traffic Safety Administration, 2008; National Institute on Alcoholism and Alcohol Abuse, 2007). This project will build on a just-completed experimental evaluation of a community intervention to reduce adolescent access to alcohol (Flewelling et al., 2012). In that study, 36 Oregon communities were randomly assigned to receive or not receive stepped up enforcement of laws regarding sale of alcohol to minors plus a program for rewarding clerks for not selling to minors. The intervention reduced youth access to alcohol. Also, communities that achieved high levels of enforcement and rewards had lower rates of youth use. However, the intervention did little to alter social influences to drink. We believe that the addition of interventions designed to mobilize peer and parent influences would alter risk factors for alcohol use that are not adequately addressed by policy interventions. Therefore, the project would evaluate a strengthened intervention that (a) increases the level of enforcement and rewards for not selling and (b) adds youth activities and family communications that have been shown to enhance social influences. Based on recent research on the value of associating not smoking with social acceptance (Gordon, Biglan, & Smolkowski, 2008), we believe that a novel peer influence intervention that associates not drinking with social acceptance can have a greater deterrent effect than interventions using more traditional harm-related and refusal skills approaches. In addition, our research has identified a brief, positive parent communication activity that does not require significant classroom time, minimizes parent-child conflict, and effectively conveys parental expectations (Biglan et al., 1996). We propose to evaluate the intervention in a randomized trial involving 36 communities. We will assess the impact of the intervention through purchase surveys, surveys of 8th- and 11th-grade students, and law enforcement records.