Hilar cholangiocarcinoma(HC) is a rare tumor.It accounts for 2/3 of the tumors of the biliary tract.Untreated,prognosis is very poor.Surgery is the only therapy that offers the possibility of cure but is technically very complex.With recent improvements in the therapeutic strategies applied by multidisciplinary teams,survival rates in the different series currently range from 25% to 45%.A group of experts devoted to HC(pathologists,gastroenterologists,radiologists,surgeons and oncologists) have reviewed and updated every open question in HC in a special issue.