Some forms of interpersonal disorders between mother and child are frequently observed within the picture of postnatal depression. This seems to be a feature of troubled maternal preoccupation, as Winnicott stated it. This is supported by clinical experience and by research on mother-child therapy, and supports the author’s specific position on causation and risk factors for development of postpartum depression. Even when DPN is linked with non specific factors (already existing depression, social and familial factors), it may be useful to assess the mother-child interaction. Mother-infant therapy may be effective in healing postpartum depression.