The integrative model of behavior prediction and priming theory were used to evaluate the effects of anti-marijuana advertisements in an experimental context. In 1 original study and 2 replications, 435 adolescents were randomly assigned to condition, and those in the experimental condition viewed 3 ads that challenged undesirable normative beliefs about marijuana use. The results showed that ad exposure had small but positive (anti-drug) effects on adolescents' considerations of the outcomes of using marijuana and their perceptions of the social normative climate surrounding marijuana use. Priming effects also were observed but generally ran counter to predictions. Implications of the findings for anti-drug campaigns are discussed. Potential explanations for the unexpected priming effects also are offered.