Drainage procedures are conceived to treat the sequels of disruption or dilatation of the pancreatic ductal system. The most common consequence of duct disruption is a pseudocyst which must be distinguished from a pseudopseudocyst. Pseudopseudocysts have no communication with the ductal system and tend to resolve spontaneously. Healing of true pseudocysts requires drainage in the majority of cases. This may be achieved by surgical or nonsurgical methods, the respective merits of which are sill under debate. Pain in chronic pancreatitis which is due to pseudocysts or ductal hypertension and duct dilatation with or without intraductal calculi is relieved by drainage in most patients. The most widely used method of ductal drainage is a longitudinal pancreaticojejunostomy. Caudal pancreaticojejunostomy is nowadays mainly used as a complementary measure to distal pancreatectomy for pseudocysts. Longitudinal pancreaticojejunostomy may fail to relieve pain in patients with an inflammatory mass in the pancreatic head. It must then be combined with resection which can be achieved by using the techniques of duodenum-preserving resection of the pancreatic head. The difference between the two techniques is not as big as it might appear at first sight.