Continuous epidural analgesia consisting of an opioid with or without a local anesthetic agent is a commonly employed technique for pain relief after thoracotomy. In this study, we prospectively evaluated the use of continuous epidural analgesia in 1,324 patients undergoing elective thoracotomy between 1987 and 1993. Epidural pain management was continued for 1 to 3 postoperative days. Patients experienced excellent pain relief, with mean visual analog pain scores of 2.4, 1.7, and 1.4 on postoperative days 1, 2, and 3, respectively. Side effects occurred most frequently in the first 24 hours postoperatively; the incidence of pruritus was 14.1%; nausea, 11.2%; hypotension, 4.3%; sedation, 3.3%; and numbness, 1.1%. Respiratory depression (< 8 breaths per minute) occurred in 1 patient who received 16 mg of supplemental morphine sulfate over a 2-hour period. The incidence of inadequate analgesia (a visual analog pain score of 7 or more persisting for 1 to 2 hours after an epidurally administered bolus) was 3.8%. The results from this study support the use of standard protocols for dosing guidelines, the treatment of inadequate analgesia, and the management of side effects. Daily evaluation by a team member of the postoperative analgesia services section of the Department of Anesthesiology enhances patient care and minimizes adverse effects.