A preliminary study was made of analgesia produced by methoxyflurane in oxygen in eleven patients undergoing surgery. Methoxyflurane was found to be safe and excellent as an analgesic agent. An associated drowsiness was also noticed, similar to that seen in the postanaesthetic period of conventional methoxyflurane anaesthesia. Methoxyflurane is compared with other agents and various theories discussed. It was felt that methoxyflurane, to date, was the agent of choice for this particular technique, especially in the geriatric, poor-risk, or emergency patient.