Studies using the Dexamethasone Suppression Test (DST) in depression showed rapid elimination of dexamethasone in association with non-suppression. To circumvent this phenomenon, cortisol was used as the suppressing agent in the Cortisol Suppression Test (CST). Cortisol and prolactin levels were estimated following both DST and CST done in series in a group of 26 patients (aged 41-60 yrs) with major depressive disorder and 29 normal subjects (aged 30-50 yrs). Results of DST were generally consistent with those obtained by other investigations showing greater nonsuppression of cortisol in depressive patients than normal subjects. Cortisol responses, however, were not suppressed following CST and similar values were obtained in depressive patients and normal subjects. Prolactin response to CST was significantly greater in depressive patients than normal subjects.