DESCRIPTION: (Applicant's Abstract) This project will evaluate a brief intervention strategy to reduce marijuana use, marijuana-related problems, marijuana outcome expectancies and increase perceived harmfulness of marijuana use among college students. The current application seeks to identify marijuana-related problems experienced by students and judged by students to be undesirable consequences of marijuana use. Students will then be asked to predict the frequency and type of marijuana-related problems they expect to experience during the following 3-week period. This explicit priming task requires students to generate cognitions regarding negative consequences of drug use and their own behavior. This strategy has demonstrated effectiveness in reducing alcohol consumption and alcohol-related problems among the same subject population. Four prior pilot studies have demonstrated that when students are asked to make similar predictions regarding alcohol-related problems they later report a decrease in alcohol consumption, alcohol-related problems and outcome expectancies. Pilot data at the proposed site indicates 45% of the students have tried marijuana and fewer than 20% perceive a great risk for occasional use of marijuana. The proposed project will use an experimental design over a 2-year period involving approximately 1300 college students at a small liberal arts college. Initially, a measure of negative consequences regarding marijuana use will be developed and validated. This measure will then be used in an experimental design comparing an intervention and control group on several dependent measures over a 4-month period. A technique to reduce marijuana use among college age youth will have a significant impact on the drug problem at college campuses.