Thirty patients were identified as having primary common duct stones. Criteria for diagnosis included at least a two year symptom free interval following cholecystectomy; soft, light brown stones or sludge present in the common duct; and the absence of a long cystic duct remnant or a biliary stricture from the previous surgery. The average age of the 30 patients was 66 years. The interval between cholecystectomy and the diagnosis of primary common duct stones averaged 12 years. Acute cholangitis was a frequent mode of presentation. At the time of surgery the bile duct was often dilated out of proportion to the serum bilirubin. In only one of the 30 patients was ampullary stenosis present. Twenty-six of the 30 patients had only stone extraction and insertion of a T tube for treatment of their primary common duct stones. Twenty-two of the 26 were followed for an average of four years and nine months with no evidence of recurrent stones in 82% (18/22). Four developed recurrent primary common duct stones one, five, five, and 7 years later. It is concluded that most patients with primary common duct stones do well after stone extraction alone.