This multidimensional approach emphasizes the unique feelings, thoughts, and behaviors of the individuals within the family system as well as the interactional patterns that occur within the system. Two issues are the focus of this endeavor: the role of the adolescent's family group in the development and maintenance of adolescent substance abuse and how these developmental and contextual factors can be incorporated into and addressed within a multidimensional treatment for adolescent substance abuse. The onset and progression of adolescent substance abuse is determined by the interaction of individual, family, peer, and community variables; therefore, interventions must occur at several levels of the adolescent's functioning. The family-based model described in this chapter was developed specifically to address the multiple forces that influence the adolescent. Critical changes within the subsystems of the individual adolescent, individual parents, parent-adolescent interactions, and extrafamilial subsystems must occur in order to stop the cycle of chronic problem behaviors and substance abuse. In discussing family risk factors for adolescent drug use and antisocial behavior, the authors focus on ineffective child-rearing practices, family discord, and poor parent-adolescent relations. In describing interventions with the multiple subsystems that influence adolescent maladaptive behavior, the authors address specific therapeutic guidelines in individual work with the adolescent, individual work with parents, and bringing parents and adolescents together. In conducting such therapeutic work, the therapist must have a thorough knowledge of the developmental issues of the adolescent period, family risk factors for adolescent substance abuse problems, and the transformations that typically occur in the parent-adolescent relationship, including changes in group cohesion in the family. 30 references