This study investigated the influences of peer and parent variables on alcohol use and problems in a sample of late adolescents in the summer immediately prior to entry into college. Participants (N = 556) completed a mail survey assessing peer influences (alcohol offers, social modeling, perceived norms), parental behaviors (nurturance, monitoring), and attitudes and values (disapproval for heavy drinking, permissiveness for drinking), and alcohol use and alcohol-related consequences. Hierarchical regression analyses indicated significant associations between both peer and parental influences and alcohol involvement, and showed that parental influences moderated peer-influence-drinking behavior, such that higher levels of perceived parental involvement were associated with weaker relations between peer influences and alcohol use and problems. These findings suggest that parents continue to exert an influential role in late adolescent drinking behavior.