IN SPITE of the fact that rabies has long been recognized as a virus disease, that more experimental work has been carried out on this disease than on any other human illness of virus etiology, and in spite of the existence of a prophylactic vaccine for the past 70 years, nevertheless there continues to be a rabies problem in most parts of the world including the United States. Although the number of animals reported annually as rabid in this country varies between 6,000 and 10,000 it is estimated that those reported represent only a small proportion—perhaps only a third—of the actual number. However, with only 10 to 20 human deaths each year due to rabies it would appear that this disease is of minor importance among the health problems of our human population, yet as many as 50,000 individuals receive antirabies prophylaxis each year. A long range program aimed at the elimination of rabies as a public health problem in any area is actually a veterinary and wildlife rather than a medical problem, because man represents the end of the line in the ecology and persistence of rabies. In other words, if rabies did not occur in animals there would be no medical problems as regards humans with this disease. The present situation in the United States concerning the prevalence and distribution of rabies and the detection of the animal reservoir is quite a bit different from what it was 25 on even 10 years ago. For years the dog has been the chief source of exposure of humans to rabies, and because of his unique relationships to man will probably continue to be so.