Introduction Since the initial report of peptic ulcer in children 126 years ago,9 approximately 500 cases of duodenal and gastric ulcer in children have been recorded. The occurrence of peptic ulcer in children thus is generally appreciated. However, the clinical manifestations of peptic ulcer in the very young, the response to treatment, and the ultimate course of the disease have not been described extensively. The purpose of this paper is to record the experience with peptic ulcer in children from the ages of newborn to 15 years, at the University of Chicago, observed during the period 1936 to 1958. Incidence.—Peptic ulceration is infrequent during infancy1,6,34 but may develop among the newborn, as evidenced by the occurrence of melena neonatorum ascribed to ulcer6 and the existence of perforated intrauterine gastroduodenal ulcer, cited by García-Moreno.13 However, increasing awareness of the possibility would increase the recognition of the