Curative treatment of Klatskin tumors by radical surgical procedures with surgical preparation distant to the tumor region results in 5-year survival rates of 30-50%. This requires mandatory en bloc liver resection and resection of the extrahepatic bile duct often together with vascular resection. Nevertheless, the ideal safety margin of 0.5-1 cm remote from the macroscopic tumor extensions cannot be achieved in all cases. Based on hilar anatomy the probability of an adequate safety margin is higher using extended right hemihepatectomy together with portal vein resection compared to left hemihepatectomy. However, due to severe atrophy of the left liver lobe solely left-sided hepatectomy is feasible in some patients. In cases of eligibility for both procedures right hemihepatectomy is preferentially used due to the higher oncological radicality if sufficient liver function is present. Postoperative hepatic insufficiency and bile leakage after demanding biliary reconstruction, often with several small orifices, contribute to the postoperative complication rate of this complex surgical disease pattern.