A randomized study of 96 women undergoing hysterectomy was used to compare two anaesthetic techniques: flunitrazepam, ketamine and nitrous oxide in oxygen; and pethidine, thiopentone, nitrous oxide in oxygen and halothane. The techniques exerted small, but significantly different influences on heart rate and arterial pressure. Significantly more patients complained of nausea and vomiting on awakening after inhalation anaesthesia. Amnesia after operation lasted significantly longer after flunitrazepam combined with ketamine and nitrous oxide in oxygen.