Thirty-seven women undergoing elective cholecystectomy were randomised into two groups, receiving either lumbar epidural morphine (group L) or epidural morphine via the thoracic route (group T). The effect on pain relief was assessed by a visual analogue scale and included both resting pain and 'provoked' pain. Respiratory parameters (PEF, FEVI and FVC) were also studied. The patients were investigated preoperatively, and 4, 6, 12 and 24 hours after the start of surgery. No significant difference was observed between the groups concerning pain relief or respiratory performance. We conclude that after cholecystectomy lumbar epidural morphine is as effective as thoracic epidural morphine in relieving postoperative pain.