Objective: To describe an innovative treatment for adolescent marijuana abuse and provide initial information about its feasibility, acceptability, and potential efficacy. Method: Provided an intervention composed of (1) a clinic-administered, abstinence-based incentive program; (2) parent-directed contingency management targeting substance use and conduct problems; (3) a clinic-administered incentive program for parent participation; and (4) individual cognitive-behavioral therapy for adolescents. Data are presented for 19 adolescents, age 15-18 years. Measures of substance use, psychopathology, and parenting were collected before and after the 14-week treatment. Substance use measures were also collected 1 month post-treatment. Substance use was monitored by twice-weekly urine and breath testing. An intent-to-treat model was used. Results: Adolescents and parents attended an average of 10.3 and 10.6 of 14 sessions, respectively. Substance use, externalizing behaviors, and negative parenting behaviors decreased by treatment end. Urine testing indicated that abstinence increased from 37% at intake to 74% at treatment end (z value = 2.28, p = .02) and that 53% of adolescents were abstinent 30 days post-treatment. Conclusions: Preliminary data provide support for the feasibility and acceptability of a family-based, contingency management model to treat adolescent substance use and conduct problems. Controlled efficacy studies with larger samples are needed. J. Am. Acad. Child Adolesc. Psychiatry, 2005;44(6):513-521. Key Words: contingency management, adolescent marijuana abuse.