Through an examination of moderator or contingent relationships, this study replicated research by Curran in 1997 and 2000 on interactions of sensation-seeking or risk taking adolescents with peer influence variables and extended Curran’s work by examining sensation-seeking interactions with posited protective factors that include perceived harm of use and personal aspirations, theorized to lead to involvement with drug-using peer groups. The central proposition of this study was that low sensation-seekers were likely to resist pressures from risk-taking peer, whereas high sensation-seekers would be motivated to comply. The question presented: were there significant interactions between sensation-seeking and alienation from school or family on marijuana and cigarette use? It was hypothesized that concurrent effects of peer influence and protective cognitive variables on marijuana and cigarette use were contingent on adolescent sensation-seeking. To test the hypothesis, a survey was given to eighth graders (n=3,127) in 1999-2000 in 20 United States middle and junior high schools. The major predictions of the study were supported. Key findings include: (1) the effects of interactions of sensation-seeking on marijuana use and cigarette use cannot be ignored and (2) the pattern of interactions was consistent with predictions for the social influence variables. The interactions indicate that low sensation-seeking adolescents appear in most cases to be at relatively low risk even in the presence of peer risk factors or in the absence of cognitive protective factors. These findings indicate that high and moderate sensation-seekers should be the primary audience for substance use prevention efforts for young adolescents. References