• Rheumatic fever has been disappearing in the United States, especially during the past two decades. In the past two years, however, there have been 40 patients seen at the Columbus (Ohio) Children's Hospital diagnosed as having acute rheumatic fever, in marked contrast to the infrequency during the preceding ten years. Twenty of the 40 patients had carditis. Five of these patients were suffering from heart failure, and there was one death. The cause for this outbreak has not yet been found, but some possible causes are discussed. A possible nationwide resurgence of this disease may be heralded by our experience and that of others.