Thomas Countryman

Thomas Countryman is Board Chairman of the Arms Control Association. He was the acting undersecretary of state for arms control and international security. He served for 35 years as a member of the U.S. Foreign Service until January 2017, achieving the rank of minister-counselor, and was appointed in October 2016 to the position of acting undersecretary of state. He simultaneously served as assistant secretary of state for international security and nonproliferation, a position he had held since September 2011.