Depression has a profound impact on parameters of interpersonal behaviour (Lewinsohn et al. 1970; Libert & Lewinsohn, 1973; Teasdale et al. 1980). Studies of healthy mother–infant dyads have demonstrated that infants are highly sensitive to their interpersonal environment (Murray, 1988). It is, therefore, likely that postpartum depression, by virtue of its impact on maternal interpersonal functioning, will disrupt normal infant engagements with the mother and, as a consequence, impair infant developmental progress. In recent years a considerable body of research surrounding this question has accumulated.