Acute pancreatitis in North-East Scotland from January 1983 to December 1985 was examined. The criteria for diagnosis were a serum amylase greater than 1000 units/l with a consistent clinical presentation, or acute pancreatitis confirmed at laparotomy or post mortem. All serum amylase assays were performed in one regional laboratory. The commonly used diagnostic coding search for pancreatitis yielded only half the cases found. We identified 378 episodes of acute pancreatitis (196 males and 182 females). The mean annual incidence for first attacks of acute pancreatitis was 242 per million of the population. The commonest aetiology was biliary tract disease (30 per cent of males and 53 per cent of females). Alcohol related pancreatitis occurred in 26.5 per cent of males but only 3 per cent of females. Complications included 26 pseudocysts, 11 pancreatic abscesses, 9 patients with respiratory failure, 11 patients with renal failure and 6 patients with disseminated intravascular coagulation.