Although laparoscopy and endoscopy have reduced the need for laparotomies in biliary tract surgery, open surgery is sometimes still needed. One case in particular is when previous operations have significantly distorted normal upper abdomen anatomy. We chose an inframesocolic entrance to the posterior peritoneum in two patients with bile duct stones, juxtapapillary duodenal diverticulum and a history of cholecystectomy and partial gastric resectioning. The duodenum was reached at the junction between the second and third section by entering the posterior peritoneum through the inferior sheet of the mesocolon, a relatively avascular area. The diverticulum was incised, the sphincter and papilla operation was performed and the bile duct stones removed. The diverticulum was then resected. Our conclusion is that in certain cases, an inframesocolic entrance can significantly reduce technical difficulties involved in re-operating through dense adhesions, minimize surgical time and blood loss and, when operating through the open diverticulum, spare an unnecessary duodenotomy.