(1) With certain exceptions, endotracheal anaesthesia is the best method for operations on the head and neck and for any other operation in which there may be a difficulty in controlling the patient's air-way. (2) Expiration should be provided for, in endotracheal anaesthesia, either by means of a second tube or by a tube of calibre sufficient to permit to-and-fro respiration. (3) Cocainization of the upper air-passages has decided advantages in endotracheal anaesthesia. (4) "Blind" intubation through the nose renders the method possible in cases where it is impossible to use a speculum. (5) The insufflation method is not specially indicated in abdominal surgery. (6) The routine use of endotracheal anaesthesia in teaching-hospitals for every class of case is detrimental to the production of sound anaesthetic knowledge in students who are likely to become general practitioners.