Reportage on the practice of hypnosurgery. Dr Perelmuter has been an anesthetist for 30 years and decided to train in hypnosis 10 years ago. Currently more than a quarter of surgical procedures that he takes part in are carried out under hypnosis. Hypnosedation results in an altered state of consciousness in the patient, who enters a hypnotic trance. It is a form of detachment which allows the patient to focus on pleasant things. Pain levels are altered, but this state fluctuates. During the procedures, theatre staff talk little so as not to disturb the patient抯 trance. The use of hypnosedation allows local anesthetics to be used instead of general ones.