- Severance Hospital clinical instructor
- Associate Professor, Catholic Kwandong University School of Medicine
- Department of Respiratory Medicine, Catholic Kwandong University International St. Mary's Hospital
- Director of the Respiratory Center at Catholic Kwandong University International St. Mary's Hospital
- Director of Outpatient Clinic, International St. Mary's Hospital, Catholic Kwandong University
- Professor at Catholic Kwandong University International St. Mary's Hospital
- Tuberculosis and Respiratory Society
