The hypothalamic-pituitary-adrenal (HPA) axis of adult patients with depression shows a pattern characterized by basal hypercortisolism, associated with an attenuated plasma ACTH response to ovine corticotropin-releasing hormone (oCRH). Most likely this hypercortisolism represents a defect at or above the level of the hypothalamus resulting in hypersecretion of CRH. Do the offspring of affectively ill mothers (unipolar and bipolar) show a similar pattern of response to CRH stimulation? The responses of children of unipolar and bipolar mothers are compared.