Continuous flow pumps are being used for the delivery of morphine sulfate to the intrathecal and epidural space for control of pain. We have encountered several patients who had a combination of pain and spasticity or who had spasticity so intense that it was the source of pain. One to two milligrams of intrathecal morphine dramatically relieved their spasticity and pain. Three such patients have subsequently undergone pump implantation with prolonged control of their spasticity. This has initiated a formal clinical investigation directed at determining the physiological mechanism of this phenomenon, as well as its long term efficacy.