Ten patients underwent implantation of intrathecal morphine catheters with subcutaneous implantation of morphine Infusaid pumps for the treatment of intractable pain of malignant origin from May 1984 to October 1985. All patients exhibited a good initial response to intrathecal morphine and developed some degree of tolerance. All patients with bony metastasis and/or lumbarsacral plexopathy developed rapid tolerance.Depressive illness was noted in all patients undergoing a psychiatric evaluation prior to institution of morphine infusion therapy. Seventy percent of patients treated could be treated on an outpatient basis after pump implantation.Complications included a pump pocket infection requiring the removal of the implanted system. There was no pump failure, respiratory depression, urinary retention, or mortality related to the use of the morphine infusion system. It is recommended that intrathecal morphine infusion be instituted when narcotics have been identified as necessary for pain relief, before the development of significant systemic tolerance.