Objective: To assess family functioning of adolescents with a history of depression, taking into account maternal history of depression. Method: Lifetime major depression was assessed with standardized interviews in an epidemiological sample of adolescent twins and their parents Family members completed questionnaires measuring family functioning. The families of three groups of adolescents were compared: ever-depressed adolescents with ever-depressed mothers (n = 37), ever-depressed adolescents with never-depressed mothers (n = 42). and never-depressed control adolescents (n = 82). Results: A greater proportion of ever-depressed adolescents had ever-depressed mothers than did control adolescents (47% versus 18%); rates of paternal depression did not differ between the two groups. Ever-depressed adolescents with ever-depressed mothers described poorer family functioning than did ever-depressed adolescents with never-depressed mothers and controls. Relative to control mothers, mothers of both groups of ever-depressed adolescents reported family difficulties, particularly in the father-adolescent relationship. Fathers' descriptions of family relationships did not differ among the three groups. Ever-depressed adolescents came disproportionately from divorced families. Conclusions: These results highlight the importance of considering parental depression in the treatment of adolescent depression and underscore the need to understand the interactional patterns in families of depressed youth, particularly those with multiple depressed members.