A cooperative national survey between 1991 and 1994 recently clarified the status of acute necrotizing pancreatitis in Japan. The overall mortality rate was 20.8%; however, the mortality rate in patients with infection was 33.3%, and the mortality rate in patients who underwent surgery was 27.4%. With regard to surgical procedures, drainage procedures (mobilization of the pancreatic bed and retroperitoneal drainage) were performed most frequently, and one third of the patients who underwent drainage procedures needed reoperation. Although debridement of the necrotic tissue (necrosectomy or resection of the pancreas) was performed in 33.3%, the mortality rate was 35.3%. There was no difference in the mortality rate between early and delayed operation. Recently two new modalities have been advocated for the management of severe acute pancreatitis in Japan. One is continuous regional arterial infusion of protease inhibitor and antibiotics, and the other is continuous hemodiafiltration. Further work is needed to establish the most effective procedures for the management of acute necrotizing pancreatitis and debridement of pancreatic infection.