Mechanical small bowel obstruction in the early postoperative period is more common than generally thought, and unless recognition and proper treatment are prompt, the mortality is high. Diagnosis in this period is often difficult because vomiting, distention, and obstipation are such common sequelae of intra-abdominal operations that the surgeon may fail to recognize their significance until the obstruction is far advanced. The presence of a low-grade fever and a slight elevation of the white blood cell count are of no diagnostic help. Also, the patient, obtunded by analgesic drugs, is not quick to perceive changes in the pain pattern and the development of new symptoms. In addition, once the presence of an obstruction is recognized, proper treatment depends upon a clear understanding of the nature of the obstruction—mechanical or paralytic. Careful repeated clinical observations and plain x-ray films of the abdomen are the most important factors that lead to a