Project ALERT is a school-based prevention program for middle or junior high school students that focuses on alcohol, tobacco, and marijuana use. It seeks to prevent adolescent nonusers from experimenting with these drugs, and to prevent youths who are already experimenting from becoming more regular users or abusers. Based on the social influence model of prevention, the program is designed to help motivate young people to avoid using drugs and to teach them the skills they need to understand and resist prodrug social influences. The curriculum is comprised of 11 lessons in the first year and 3 lessons in the second year. Lessons involve small-group activities, question-and-answer sessions, role-playing, and the rehearsal of new skills to stimulate students’ interest and participation. The content focuses on helping students understand the consequences of drug use, recognize the benefits of nonuse, build norms against use, and identify and resist prodrug pressures.