Choledochoduodenostomy is a procedure to be used as an option in certain circumstances and the decision often has to be made at the time of operation. The 2 essential criteria are a dilated common bile duct and an obstruction at its lower end. It may be used at a first operation to prevent recurrent stones if there is clear evidence of a primary duct problem, or at a second operation for recurrent stones when the existence of a duct problem is usually more certain. There are some situations in which choledochoduodenostomy is a genuine alternative to sphincteroplasty. We favor choledochoduodenostomy in obese patients, if there is difficult access to the sphincter, if there is a long stricture as in chronic pancreatitis, when there is suppurative cholangitis, or when the duct is already being explored from above. There is a variety of operative techniques using continuous or interrupted sutures, but it is inadvisable to put nonabsorbable sutures into the lumen of the bile duct. The incision in the duodenum can be longitudinal or transverse, but the duodenum must be rolled up on to the bile duct without tension. The only diet restriction after operation involves avoidance of indigestible particles such as tomato and apple skins and grape pips which may become lodged in the distal bile duct. In the worldwide experience with follow‐up periods of up to 20 years, “ascending” cholangitis has been very rare (about 1%) when the operation was performed correctly with an initial stoma size of at least 2.5 cm.