CONGENITAL hypertrophic pyloric stenosis is the most common condition requiring surgical treatment in the infant. Although it was first described by Fabricus Hildanus in 1627, intelligent interest in the abnormality did not develop until 1887, when Hirschsprung gave a convincing description of the disease. The application of surgical measures to its correction dates back to 1892, when Cordua, of Hamburg, performed jejunostomy, unsuccessfully. Subsequently, various operative procedures were tried, gastrojejunostomy being the operation most commonly employed. This carried a disturbing mortality of approximately 50 per cent. In 1907 Pierre Fredet performed what amounted to a Heineke-Mikulicz pyloroplasty in 2 cases. In 1911 Rammstedt, when confronted with unusual difficulty in closing the muscle in that type of operation, sutured the omentum over the protruding mucosa, with successful results. Thus, pyloromyotomy, which is now employed, was evolved somewhat by accident and necessity. Even though the operation is simple and almost foolproof, the