We have measured intra-ocular pressure (i.o.p.) in 20 patients anaesthetized with halothane or enflurane (0.6 MAC in oxygen) for repair of trauma to the eye. The changes in i.o.p. with halothane 0.5% were unpredictable, whereas enflurane 1% reduced intra-ocular tension consistently in all the patients studied. Enflurane is recommended as a possible alternative anaesthetic for surgery on the open eye.