The social system of the family is a major variable in the syndrome of alcoholism. The family system may generate or promote the development of alcoholism in a family member. The alcoholic behavior of a family member may disrupt and impair family system function. Although these relationships highlight important correlations between alcoholism and family function, research evidence demonstrates that the relationship is complex. Simple models of a typical alcoholic family no longer suffice. Research on four aspects of family alcoholism are reviewed: family reactivity patterns, ethnic family styles, gender of the alcoholic spouse, and stages of alcoholism. These data support the conclusion that family systems are an important variable in the genesis, consequences, and treatment of alcoholism.