En-bloc liver resection with caudate lobectomy (segmentectomy 1) is the standard procedure for hilar cholangiocarcinoma. Although its surgical mortality has been reduced below 5%, it is still a potentially hazardous operation. Complete tumor resection with negative surgical margins and safe reconstruction of bilio-enteric continuity are two principles of the surgical treatment of hilar cholangiocarcinoma. Surgeons must pay attention to the variation of the hilar structures including portal veins, hepatic arteries, and bile ducts. Three-dimensional imaging is beneficial not only for understanding anatomical variations but also for preoperative simulations. Since the U-point can be identified by both preoperative imaging and intraoperative inspection, it can be used as the landmark for the hepatectomy and the dissection point of the hilar plate. The hanging maneuver might be useful for both hepatic parenchymal dissection and bile duct dissection just right of the U-point. For safe biliary reconstruction, stay sutures in the anterior wall and transanastomotic stents may be helpful.