Only a minority of patients admitted with acute abdominal pain require urgent operation, but the identification of those who need an operation may be difficult. Many surgeons adopt a radical approach and operate when the diagnosis is doubtful, which often leads to 20 percent rate of negative findings on laparotomy. In this study, 220 patients of all ages admitted with acute abdominal pain were studied prospectively, and when the diagnosis on admission was uncertain, a policy of active observation was employed. In all, 39 percent of the patients underwent operation and only 5 percent had negative findings on laparotomy. No patient suffered as a result of this policy, which is recommended as a safe and effective approach to the management of acute abdominal pain.