The characteristics of dysfunctional and delinquent families are discussed. Behaviorally based interventions in delinquent families can be focused or broad-band. Focused approaches treat special delinquency behaviors of children such as fire-setting, stealing, drug abuse, and running away from home. Broad-band approaches treat the whole family system so that it no longer fosters or permits delinquent behavior. Three broad-band techniques include parent training, parent-child contracting, and therapist as mediator of specific conflicts. Other behavioral techniques for the treatment of dysfunctional families include marital skills training programs for spouse abuse, parent effectiveness training for families involved in child abuse and neglect, and group theapy and contracts for families involved in the sexual abuse of children. Family-based interventions must be tailored to fit individual cases. When families or individuals are targeted for ecobehavioral and broad-band treatment, special care must be taken to assess individual rights and the long-term effects of the dynamics of family behavior. When several governmental agencies are involved, the intervention must be documented and coordinated. 195 references.