✓ The author describes the many early advances in neuroanesthesiology made by pioneer neurosurgeons. Macewen first employed endotracheal intubation for anesthesia. Horsley vigorously promoted chloroform research and the development of the Vernon Harcourt regulator, the first anesthesia machine to provide safe and accurate concentrations. With the aid of the Harcourt inhaler he made many brilliant neuroanesthetic observations. Codman and Cushing collaborated on the first intraoperative anesthetic records while still medical students. Cushing later introduced the Riva-Rocci blood pressure apparatus to the United States. His early intracranial procedures were performed under ether narcosis, but Cushing's experiences during World War I led him to adopt local anesthesia for the remainder of his career. The first clinical application of insufflation anesthesia was made by Elsberg. Frazier introduced rectal ether for neurosurgical procedures. Local anesthesia enjoyed its greatest popularity during the 1920's and 1930's. Endotracheal intubation and complete respiratory control were accepted by most neurosurgical clinics around the time of World War II.