Although there is no debate that patients with peritonitis or hemodynamic instability should undergo urgent laparotomy after penetrating injury to the abdomen, it is also clear that certain stable patients without peritonitis may be managed without the need for an operation. The practice of deciding which patients may not need surgery after penetrating abdominal wounds has been termed “non-operative management.” This practice has been readily accepted during the past few decades with regard to abdominal stab wounds; however, controversy persists regarding when a conservative management approach is appropriate for penetrating gunshot wounds. Abdominal gunshot injuries are still commonly treated with mandatory exploration because of the multiple reports emphasizing a high incidence of significant injuries and the complications that result from a missed injury or a delayed diagnosis. The enthusiasm for nonoperative management in patients with penetrating abdominal trauma is based on a relatively high incidence of nontherapeutic or negative laparotomy from civilian low-velocity injuries. Reports on the incidence of unnecessary laparotomies range from 23% to 53% for patients with stab wounds and 5.3%-27% for patients with gunshot wounds.1 Complications develop in 2.5%-41% of all trauma patients undergoing unnecessary laparotomy, and small bowel obstruction, pneumothorax, ileus, wound infection, myocardial infarction, visceral injury, and even death have been reported secondary to unnecessary laparotomy. 2,3 The process of selecting patients for nonoperative management requires considering several factors: the specific mechanism (stab vs gunshot), the velocity of the inflicting agent (low vs high), and the different areas of the torso that may be affected (intraperitoneal, retroperitoneal, and thoracoabdominal). In developing management strategies for penetrating abdominal trauma, it is helpful to divide the abdomen into regions: the anterior abdomen (from xiphoid to pubis, between the anterior axillary lines); the flank and back (posterior to the anterior axillary lines); and the thoracoabdomen (from the nipple line to the costal margin). The approach for each of these regions varies. If the patient is selected for initial nonoperative management, additional diagnostic methods often become necessary. An abdominopelvic multidetector computed tomography is now strongly regarded as the main diagnostic tool to facilitate initial management decisions. However, other methods that can be considered include diagnostic peritoneal lavage, ultrasonography (US), and laparoscopy.