The purpose of this study is to evaluate the therapeutic efficacy of a cognitive-behavioral group treatment for depression in adolescents. Over the course of the study, 192 depressed adolescents and their parents will be treated. Comprehensive assessment on diagnostic and depression-related psychosocial variables will be conducted at entry, at posttreatment, and at follow-up points to 2 years posttreatment. Subjects will be randomly assigned to three Treatment and three Follow-Up Conditions. In Treatment Condition 1, both the adolescents and their parents will be treated. In Treatment Condition 2 only the adolescents will be treated. Condition 3 is a wait-list control. Follow-Up Condition 1 provides infrequent posttreatment monitoring and assessment (at 12 and 24 months posttreatment). Follow-Up Condition 2 provides more frequent monitoring and assessment (at 4, 8, 12, 16, 20, and 24 months) posttreatment. Follow-up Condition 3 adds an individual session with the therapist for the adolescent and parents at each of the assessment points. Prognostic variables to be included are those which have emerged as predictive of treatment outcome with adults, but which have not been tested with adolescents. The long-term goals of the proposed research are to (a) contribute to the development of cost-effective methods for the treatment of depression in adolescents; (b) contribute to the knowledge about the psychosocial variables associated with the course of depression in adolescents; and (c) contribute to the recognition of depression among adolescents as a more serious public health problem than is currently recognized (cf., the increasing rate of adolescent suicide).