- Severance Hospital Intern
- Severance Hospital Resident
- Director of Psychiatry at Konyang University Hospital
- Director of Planning and Public Relations, Incheon St. Mary's Hospital
- Director of the International Medical Cooperation Center at Catholic Kwandong University International St. Mary’s Hospital
- Director of Shar Royal Hospital, International St. Mary's Hospital, Catholic Kwandong University
- Current Professor at Catholic Kwandong University International St. Mary's Hospital
- Served as Director of the Mental Health Committee of the Korean Neuropsychiatric Association
- Served as Chairman of the Korean Society of Addiction Psychiatry
- Current President, Korea Suicide Prevention Association