This paper reports the authors' observations on fifteen families in which a young adult member had been diagnosed as manic-depressive. All families were seen in systemic family therapy, with intervals of four to six weeks between sessions. The circular questioning method developed by Selvini-Palazzoli [1] and her team was widely employed. All families could be described as extremely rigid and bound-up systems characterized by a "restrictive parental complementarity," typical dynamics of reciprocal delegation, and certain cognitive features and shared assumptions. These "manic-depressive" families show similarities as well as differences when compared with families with schizophrenic members (i.e., "schizo-present" families). Finally, some therapeutic implications of this view and approach are developed.