DESCRIPTION: (Applicant's Abstract) Runaway shelters document high levels of substance abuse among runaway youth, at least double that of school youth and there is increasing public health concern for this group over the associated risk for AIDS. Runaway youth present a constellation of problems, and research suggests that this population may be unique in the range and intensity of associated problems. The abuse and neglect experienced by these youth on the streets is compounded by societal neglect in addressing the needs of a population sorely requiring intervention. Most studies to date have collected self-report data on the family and social history; virtually no research has examined treatment effectiveness with this population. Given the void of treatment outcome research with these youths, and the high level of risk for health and psychological problems, there is a great need for identifying potent interventions. Although research supports the effectiveness of behavioral family therapy in reducing substance abuse among adolescents, no study has systematically applied and evaluated a family-based intervention with runaways. The proposed study is a Stage 1 behavioral treatment development project designed to examine the effectiveness of a multi-systemic behavioral family-based intervention in reducing substance use and HIV risk behaviors, while increasing family and psychological functioning in a sample of runaway adolescents. The effectiveness of booster sessions in maintaining treatment gains will be examined, and an intensive engagement strategy will be employed.