Alcohol and drug problems affect not only those using these substances but also family members of the substance user. In this review evidence of the negative impacts substance misuse may have upon families are examined, following which family-focused interventions are reviewed. Several family-focused interventions have been developed. They can be broadly grouped into three types: (1) working with family members to promote the entry and engagement of substance misusers into treatment; (2) joint involvement of family members and substance misusing relatives in the treatment of the latter; and (3) interventions responding to the needs of the family members in their own right. The evidence base for each of the three types is reviewed. Despite methodological weaknesses in this area, a number of conclusions can be advanced that support wider use of family focused interventions in routine practice. Future research needs to focus on (1) pragmatic trials that are more representative of routine clinical settings; (2) cost-effectiveness analyses, in terms of treatment costs and the impact of interventions on costs to society; (3) explore treatment process; and (4) make use of qualitative methods. In addition, there is a need to define more clearly the conceptual underpinnings of the family intervention under study.