Acute pancreatitis is a common disease most frequently caused by gallstone disease or excess alcohol ingestion. Diagnosis is usually based on characteristic symptoms, often in conjunction with elevated serum pancreatic enzymes. Imaging is not always necessary, but may be performed for many reasons, such as to confirm a diagnosis of pancreatitis, rule out other causes of abdominal pain, elucidate the cause of pancreatitis, or to evaluate for complications such as necrosis or pseudocysts. Though the majority of patients will have mild, self‐limiting disease, some will develop severe disease associated with organ failure. These patients are at risk to develop complications from ongoing pancreatic inflammation such as pancreatic necrosis, fluid collections, pseudocysts, and pancreatic duct disruption. Validated scoring systems can help predict the severity of pancreatitis, and thus, guide monitoring and intervention.Treatment of acute pancreatitis involves supportive care with fluid replacement, pain control, and controlled initiation of regular food intake. Prophylactic antibiotics are not recommended in acute pancreatitis if there is no evidence of pancreatic infection. In patients who fail to improve, further evaluation is necessary to assess for complications that require intervention such as pseudocysts or pancreatic necrosis. Endoscopy, including ERCP and EUS, and/or cholecystectomy may be indicated in the appropriate clinical setting. Ultimately, the management of the patient with severe acute pancreatitis will require a multidisciplinary approach. Journal of Hospital Medicine 2010;5:241–250. © 2010 Society of Hospital Medicine.