Objective: To assess the effectiveness of the long acting local anesthetic (0.25% ropivacaine) intermittently administered through an extrapleural paravertebral catheter versus a thoracic epidural catheter on postthoracotomy pain relief. Patients and Methods: Forty patients undergoing elective posterolateral thoracotomy during the period between July 2001 and August 2002 were prospectively studied. They were randomly allocated into two groups (A and B) of 20 patients each. Group A patients received an epidural-type catheter inserted by the surgeon into an extrapleural pocket extending for 2 to 3 intercostal spaces both above and below the thoracotomy incision alongside the vertebral column by the conclusion of operation. A bolus dose of 15 ml of 0.25% ropivacaine analgesia was given during chest closure.Group B patients received a thoracic epidural catheter inserted by the anesthesiologist at T5-6 or T6-7 interspace before induction of anesthesia. A bolus dose of 15 ml of 0.25% ropivacaine analgesia was given after confirming the correct position of the epidural catheter. Postoperatively, patients in both groups were intermittently administered 25 ml of 0.25% ropivacaine analgesia at 6 hourly intervals for 3 successive days. Pain scores (verbal rating scale), requirement of additional analgesia (NSAID), pulmonary function test, shoulder range of motion as well as any complication encountered were assessed and compared in both groups. Results: Excluding the immediate postoperative arousal period, the extrapleural analgesia provided better pain control than the thoracic epidural analgesia in the form of less mean values of the verbal rating scale (VRS). Also, the extrapleural analgesia provided more rapid improvement of pulmonary functions, progressive increase of the shoulder range of motion (SROM) as well as less analgesic requirements in comparison to the thoracic epidural analgesia. However these differences were statistically non-significant (P>0.05). Side effects namely, hypotension, bradycardia and atelectasis were troublesome only in the thoracic epidural analgesia group. There was no mortality in either group. Conclusion: Extrapleural paravertebral catheter technique is a valuable alternative to the thoracic epidural technique for post-thoracotomy pain relief. It is easy to perform by the surgeon at the conclusion of operation without complications or side effects. It should be considered as the first choice alternative for post-thoracotomy pain control.