Young marijuana abusers rarely seek treatment themselves and are difficult to engage in treatment when referred by social agencies. To evaluate treatment engagement strategies in this population, 65 young probation-referred marijuana abusers were randomly assigned to either three-session motivational enhancement therapy (MET alone) or three-session MET plus contingency management (MET/CM), with vouchers for treatment attendance. A significantly higher number of participants in the MET/CM condition completed the three-session intervention as compared with MET alone. Participants in both conditions reported significant reductions in marijuana use and improvement in legal problems. These findings suggest that young marijuana abusers benefit from scientifically validated treatments.