This paper presents clinical data from a research study designed to examine the relation between alcohol consumption and interactional behavior in "alcoholic couples". The central innovative feature of the study was the simultaneous admission to an inpatient setting of up to three couples, one or both members of which was alcoholic. The in-patient experience was part of an intensive, six-week, multiple-couples, group-therapy program. During hospitalization couples were encouraged to reproduce as closely as possible their usual drinking patterns and interactional behavior. Therapists utilized observations of interactional behavior during intoxication and sobriety to formulate central interactional and psychological issues for each couple. The authors utilized these same observations to develop the interactional model of alcoholism in families that is presented in detail in this paper. This model is an extension of earlier work delimiting an interactional theory of alcoholism based on general systems concepts.