Physiologic state notwithstanding, clinical assessment should at minimum include a detailed medical history including prior operative interventions as well as an appropriate physical exam and laboratory workup. Past medical history includes prior endoscopic evaluation such as colonoscopy. This is particularly important in patients who present with perforation secondary to large bowel obstruction raising the possibility of a neoplastic etiology in the absence of a prior endoscopic evalua­tion. Hemodynamic stability often affords more time for a detailed clinical history and physical exam habitually supplemented by a CT scan of the abdomen and pel­vis. Identication of free air or uid throughout the abdomen may give further clues to the classication of the presenting diverticular disease with categorization into Hinchey I–IV (Box 28.1) and as such dictate further management. In the absence of free uid or diffuse air throughout the abdomen, nonoperative management should be considered as the preferred pathway. Failure to respond to medical management should trigger conversion to an operative approach. Patients with presumed Hinchey III diverticular disease may be considered for laparoscopic lavage with the under­standing that delineation between Hinchey III and IV can be challenging and may require conversion to a bowel resection either by laparoscopy or open. Other preop­erative considerations may include ureteral stents depending on availability at the time of surgery.