Twenty-seven patients with 32 pancreatic pseudocysts have been seen during the past 10 years at St George's Hospital, London. Two of the pseudocysts were found in unusual positions--one in the right inguinal canal and the other one in the porta hepatis. Approximately half of the pseudocysts in this series followed biliary-induced pancreatitis. The various clinical presentations are reported and the surgical treatment is discussed. Internal drainage is the most effective treatment and in the majority of cases transgastric cystogastrostomy via a tube is the procedure of choice. One death occurred, an overall mortality rate of 3-1 per cent.