Nineteen male and female patients with cystic dilation of the common bile duct were treated by total removal of the choledochal cyst and reconstruction using a Roux-en-Y end to side hepaticojejunostomy. Follow-up study was 18 years for some patients. Our data suggest that this disease is highly correlated with an anomalous pancreaticobiliary junction and its sequelae, and that previous treatment by internal drainage is not uniformly successful. After radical surgical treatment and reconstruction, no deaths occurred in any of the patients. All early complications were treated with success by conservative means. With the use of the criteria of Alonso-Lej, there was a clinically significant shift in the status of the choledochal cyst from type 2 before operation to type 1 after operation. Our long term experience with this group of patients leads us to recommend total excision of the choledochal cyst and end to side hepaticojejunostomy for treating patients with cystic dilation of the common bile duct.