Since the first report in 1846 on the use of anesthesia for a surgical procedure, deaths have occurred with practically every agent and technique used. Those mishaps of which we are aware are probably just a small segment of those that have actually occurred, since presently there is no widely used method for identifying anesthesia-associated deaths. Several sources of information are available, including the United States National Center for Health Statistics and articles in the medical literature. Neither of these encompasses more than a fraction of the total experience; in addition, the population upon which most reports are based and the number of anesthesias involved are usually not available as a denominator in determining the incidence of mishaps and the magnitude of the problem. Extrapolating from data from community anesthesia study committees and from population and operative figures, we can estimate that there are over 5,000 deaths associated with anesthesia in this country each year. This is 3 times as many as are caused by muscular dystrophy and multiple sclerosis, 15 times as many as with sickle cell anemia, 20 times as many as with myasthenia gravis and 40 times as many with poliomyelitis. We thus must recognize that anesthesia is an iatrogenic disease that deserves serious attention as a public health problem.