We reviewed 187 cases of documented neonatal necrotizing enterocolitis (NEC) from 1976 to 1988. Of these patients, 111 infants underwent celiotomy for acute surgical complications. The following protocol of operative indications was employed: pneumoperitoneum, localized mass, abdominal wall erythema, portal venous air, and clinical deterioration, singly or in any combination. Clinical deterioration was defined as falling platelet count, rising or falling white blood cell count, left shift in the myeloid series, persistently or progressively low pH, and increasing frequency of apnea or bradycardia. Overall mortality was 15% (28 of 187). For the patients who underwent celiotomy, all had histologic confirmation of NEC. Ninety-five had localized disease, and 16 had diffuse disease. All of the former had resection and diverting enterostomy with 85 (89.5%) surviving; none with diffuse disease survived, P less than 0.0001. Forty-one infants with NEC weighed less than 1,000 g; 25 underwent surgery and 15 (60%) survived. Fifty-one of the 159 surviving neonates (32%) developed intestinal strictures. All neonates with strictures have had resection and successful reconstruction of their gastrointestinal tract. These indications and surgical principles resulted in a high degree of diagnostic accuracy and a low degree of surgical mortality.