The first laser was developed by Maiman in 1960 using a ruby crystal as an active medium. The word laser is an acronym for Light Amplification by Stimulated Emission of Radiation and this light beam can be focused to a small spot, resulting in precisely controlled coagulation, incision, or vaporization of tissue. The two types of lasers commonly used for airway surgery are the carbon dioxide laser and the neodymium-yttrium-aluminum-garnet (Nd YAG) laser. The light of the former will easily vaporize tissue and can be used to make a precise incision with minimal damage to adjacent tissue and the light of the latter can be conducted through fiberoptic instruments and permits successful endoscopic resection of untreatable recurrent or persistent malignant diseases of the major airways. Airway and endotracheal tube fire are the most feared hazard during laser surgery of the airway. The risk of fire depends on the nature of the tube material, the gaseous milieu, the beam wattage, and its mode of operation. The surgeon should use the laser intermittently at moderate wattage (15W) in a pulsed mode to prevent excessive heat field buildup and tissue dessication. For safe anesthetic management, nitrous oxide should be avoided, and a mixture of oxygen (25%) and air should be used or helium, which is a known flammability quencher may be used during airway laser surgery at a 60 percent He 40 percent 0, mix. Due to the increase in CO2laser treatments, we reviewed the clinical records of 150 patients in whom CO2laser surgery was performed and the anesthetic management was evaluated from April 1987 to December 1988. 1) A total of 150 patients were evaluated, including 81 males and 69 females ranging in age from 10 months to 74 years and averaging 41 years. 2) The operations performed were vocal nodule (26.0%), vocal polyp (16.0%), laryngeal papilloma (16.0%), etc. 3) The methods for keeping the airway open during general anesthesia were orotracheal intubation (67.5%) and intubation through the tracheostomy stoma (32.5%). 4) The main anesthetic agents were halothane, enflurane, and fentanyl. The anesthesia and surgery lasted 60.9+-24.0minutes and 44.5+-28.5 minutes on average respectively. 5) Laryngoscopic laser surgery was carried out in 127 patients (84.7%), bronchoscopic surgery in 14 patients (9.3%) and surgery using a handpiece in only 8 patients (6.0%). 6) Complications were found in 3 cases, including endotracheal cuff ignition and pneumomedias-timum.