Though peer socialization theories are prominent in the adolescent substance use literature, variability in the degree to which adolescents are vulnerable to peer influence is likely, and few studies have examined this issue. This study examines the association between perceived peer substance use/approval of substance use and adolescent intentions to initiate alcohol and cigarette use and how social goals moderate this relationship. Results support the moderating role of social goals and suggest important differences across alcohol and cigarette use. Peer use and approval of cigarette use is associated with future intentions to smoke for adolescents with strong agentic goals, and peer use and approval of alcohol is associated with intentions to drink for adolescents with strong communal goals. These findings suggest that adolescent substance use theories and prevention programs focusing on peer socialization should consider individual differences in social goals and potential differences in peer influence across drugs. (Contains 1 note, 4 tables, and 2 figures.)