Project Summary The negative impact of heavy episodic drinking (HED) among college students continues to be a major public health issue, and students who are members of fraternities and sororities (Greek members) are at particularly greater risk for experiencing negative alcohol consequences due to frequent HED. Individual-level alcohol interventions have limited efficacy among Greek members, which may be because these approaches do not directly account for the greater social ecological and developmental factors which play a significant role in drinking behavior. Young adulthood is marked by an emphasis on developing and maintaining social bonds, and alcohol use is an integral part of social interactions in the Greek environment. This study integrates developmental and behavioral economic models of alcohol use to develop and test an environmental intervention addressing HED and alcohol consequences. The intervention focuses on increasing the availability of and engagement in rewarding alcohol-free social activities, providing alternatives to drinking events for building social connections. Human-centered design principles will incorporate the perspectives of Greek members in the intervention development process to increase usability and contextual fit. This innovative study will proceed in three phases following the Discover, Design/Build, Test framework. Discover Phase: Greek members' perspectives and needs on social activity engagement will be identified by conducting qualitative interviews (N = 30) and a quantitative survey (N = 925) to better understand the intervention setting and the context of social activity engagement in the Greek community. Design/Build Phase: The intervention will be developed and refined in collaboration with Greek members involving co-creation sessions and iterative feasibility and acceptability testing. Test Phase: Feasibility and acceptability of the intervention and the impact of the intervention on alcohol outcomes will be evaluated using a pre-post design with two cohorts of six chapters over two years. This Career Development Award will support the investigator's development as an independent researcher focusing on the development of alcohol interventions addressing reward processes among young adults who engage in high-risk alcohol use. The investigator's long-term career goals will be achieved through training in 1) developmental and reinforcement-based models of young adult high-risk alcohol use, 2) research methods for measuring and increasing substance-free reinforcement, 3) developing collaborative relationships with community partners, and 4) research approaches that emphasize acceptability, effectiveness, and potential for successful implementation. Dr. Lehinger's career goals and project are consistent with NIAAA's prevention goals of a) developing and evaluating strategies to prevent and reduce alcohol misuse among young adults and b) evaluating the effectiveness and implementation of environmental in...