1988.03 1989.02 Seoul National University Hospital, Korea Internship
1989.03 1993.02 Seoul National University Hospital, Korea Residency
1996.05 1997.08 Department of General Surgery, Ewah Women's University Mokdong Hospital Fellow
1997.01 1997.05 University of Maryland Visiting fellow
1997.09 1999.08 Department of General Sugery College of Medilcine, Ewha Women's University Instructor
1999.09 2002.08 Department of General Sugery College of Medilcine, Ewha Women's University Assistant Professor
2002.09 present Center for Grastric Cancer, National Cancer Center Staff
2006.03 present Gastric Center Branch, Division of Common Cancers, Research Institute Chief Scientist
2006.08 present Center for Grastric Cancer, National Cancer Center Head
2007.12 2009.12 Gastric Cancer Branch, Research Institute, National Cancer Center Chief
2007.12 2009.01 Division of Translational ＆ Clinical Research, National Cancer Center Head
2008.01 2008.02 Hospital Ambroise Pare Visiting professor
2008.01 2008.02 Regina Elena National Cancer Center Visiting professor
2008.01 2008.02 Technische Universitat Munchen Visiting professor
2008.12 2010.08 Center for Cancer Prevention ＆ Detection, National Cancer Center Head
2009.08 2015.02 Department of Surgery, Hospital, National Cancer Center Chief
2012.01 present Gastric Cancer Branch, Research Institute, National Cancer Center Chief
2014.03 present Department of Cancer Control and Policy, Graduate School of Cancer Science & Policy Professor
2015.02 2017.02 Graduate School of Cancer Science and Policy Professor
2017.03 present Department of Cancer Control and Population Health,Graduate School of Cancer Science and Policy Professor
2019.02 present Center for Gastric Cancer, National Cancer Center Adjunct
2021.02 present Research Institute, National Cancer Center Director