SUMMARY. In a study of four patients undergoing major gynaecological surgery under epidural analgesia together with general anaesthesia, it was found that epidural analgesia delayed but did not prevent a normal adrenocortical response to surgery. In the absence of surgery, epidural analgesia had no effect on plasma cortisol levels. It was concluded that complete alleviation of postoperative pain by neurogenic blockade does not prevent the normal adrenocortical response to surgery.