Over a three-year period, we have operated on 30 infants with necrotizing enterocolitis. Because of the increased experience with this lesion, we have evolved reliable guidelines for both early diagnosis and operative treatment of necrotizing enterocolitis. Initial therapy was nonsurgical in most cases and included gastrointestinal tract decompression, systemic antibiotics, and correction of fluid, electrolyte, and metabolic abnormalities. Absolute indications for surgery and thought to be prima facie evidence for bowel necrosis were (1) cellulitis of the anterior abdominal wall, (2) free intraperitoneal air, (3) a single dilated intestinal segment present on serial roentgenograms, (4) clinical deteioration in the presence of appropriate medical therapy, and (5) persistent abdominal tenderness. Although all 30 patients operated on had necrotic bowel proved at histologic examination, 21 survived (70%). All patients listed as survivors, with the exception of two, have had intestinal tract continuity reestablished and are doing well.