Ho-Jin Lee is a former Brookings expert. He is a former diplomat from the Republic of Korea (ROK) with over three decades of service. His career has covered the United States, Europe, and East Asia, and he specializes in the ROK-U.S. alliance, East Asian security, arms control and non-proliferation, and nuclear energy. He was most recently the ROK ambassador to Finland, and he has also served as ambassador to Hungary and as ranking ambassador to the United Nations. In a personal capacity, he worked for the U.N. secretary general as a member of the U.N. Advisory Board on Disarmament for five years and as its chairman in 2007.