Family, dyadic, and individual functioning were examined in 18 control families and 41 families with a history of maternal affective illness-including 26 in which husbands also had a history of psychiatric illness. Assessments of functioning, based on observed family interactions, indicated that families with a history of affective illness are more likely to have functional problems, and that problems may differ as a function of type of diagnosis and number of ill parents. Findings suggest that clinical program planning should take into account variability within groups, as well as individual competencies.