The influence of pancreatic resection on early systemic complications of acute necrotizing pancreatitis was evaluated in 84 patients. The aetiology of pancreatitis was alcohol 71 per cent, gallstones 13 per cent, alcohol plus gallstones 2 per cent, trauma 1 per cent and idiopathic 12 per cent. A total of 26 of 81 patients (32 per cent) had greater than 50 per cent pancreatic necrosis and 9 patients (11 per cent) considered to have parenchymal necrosis at operation had none shown histologically. The overall mortality was 38/84 (45 per cent) and mortality during the first postoperative week was 15/84 (18 per cent). The outcome after early and delayed operation did not differ significantly. Pancreatic resection had no beneficial effect on shock or respiratory or renal failure (respective pre-operative incidence 12 per cent, 11 per cent and 14 per cent).