Mallory Stewart

Mallory Stewart is the Executive Vice President at the Council for Strategic Risks. She was the Assistant Secretary for the Bureau of Arms Control, Deterrence, and Stability (ADS) at the U.S. Department of State from April 2022 until January 2025. At the end of her service as Assistant Secretary, Ms. Stewart received the State Department’s Distinguished Honor award and medal for her outstanding leadership. She joined the bureau after serving as a Special Assistant to the President and Senior Director for Arms Control, Disarmament, and Nonproliferation at the National Security Council from January 2021 until April 2022. Prior to joining the NSC, Ms. Stewart was the Senior Manager for Global Nuclear Security and Nonproliferation at the Center for Global Security and Cooperation in Sandia National Laboratories. While at Sandia, she led Sandia’s Cooperative Monitoring Center in its efforts to facilitate scientific engagement for global security. 

From 2015 to 2017, Ms. Stewart was Deputy Assistant Secretary of State for Emerging Security Challenges and Defense Policy in what was then called the Bureau of Arms Control, Verification and Compliance. In that role, she oversaw the Office of Emerging Security Challenges and the Office of Chemical and Biological Weapons Affairs.  

Before that, Ms. Stewart was an attorney adviser in the Department of State’s Office of the Legal Adviser, beginning in 2002. During that time, she worked on numerous legal issues related to nonproliferation sanctions, weapons of mass destruction and conventional arms control, missile defense, and outer space in the Office of Nonproliferation and Arms Control. Ms. Stewart was the State Department lawyer for the U.S. delegation that negotiated the Ballistic Missile Agreements with Poland and Romania, and she was the lead lawyer on the 2013 U.S.-Russian Framework for the Elimination of Syrian Chemical Weapons. For her work on that issue, Ms. Stewart was a recipient of the Secretary of State’s 2014 Award for Excellence in International Security Affairs. 

Ms. Stewart has also worked as an Adjunct Assistant Professor at Georgetown University’s School of Foreign Service and as an associate at the law firm of Sullivan & Cromwell. She holds an A.B. from Harvard College and a J.D. from Stanford Law School.