Prof. Haifeng Xu is an Associate Professor at the Department of Liver Surgery, Peking Union Medical College Hospital, Beijing, China. He received an M.D. from Peking Union Medical College in 2004. He was a visiting scholar at Brigham and Women's Hospital, Harvard Medical School. His research interests include the diagnosis and treatment of benign and malignant tumors of the hepatobiliary system, intra-and extrahepatic bile duct calculi, and other diseases.