KOH Seung-Hahn received a Ph.D. degree in sociology department at the University of Kentucky, Lexington in USA. Since then, Dr. KOH had been working with Jeju Research Institute(after JDI) in Jeju, thus laying out diverse policy issues such as social welfare, employment and labor policy, socio-economy. Uniquely, as a result of his endless passion and efforts, Jeju Province became a member of Global Network for Aged-Friendly City by WHO of U.N. in 2017 year. After a formal retire from JDC in the late of 2018. Dr. KOH explicitly sustained his research activities and college lectures in the sphere of social welfare and sociology in Jeju. Furthermore, in late July of 2022, he was appointed as a President of Jeju Institute for Lifelong Education and Scholarship, and has tried to revitalize local lifelong education facing the grand transition era of lifelong education. Simultaneously, Dr. KOH's efforts for coupling private resources with scholarship funds have been useful to some students that may devote to lead future Jeju development. Since April 11 last year, Dr. KOH has been often taking a role as a Chairperson of Social Contract Commission for Jeju Provincial Government, thus dealing with a variety of social conflict and human rights in Jeju.