The Assistant Secretary of State for Arms Control, Deterrence, and Stability is the head of the Bureau of Arms Control, Verification and Compliance.

Within the department, the Assistant Secretary is responsible for all matters relating to the supervision of verification and compliance with international arms control, nonproliferation, and disarmament agreements.

President Joe Biden nominated lawyer and arms control expert Mallory Stewart for the position on June 2, 2021; she was confirmed by the Senate on March 29, 2022, and was sworn in on April 18, 2022.

[2] The Assistant Secretary manages and advises the Secretary of State and the Under Secretary for Arms Control and International Security on the appropriate uses of the Key Verification Assets Fund, which supports the Department of State's preservation of critical verification assets and promotes the development of new technologies to enhance verification of existing and future arms control, nonproliferation, and disarmament treaties or agreements.

[3] The Assistant Secretary is also responsible for the President's Annual Report to Congress on Adherence to and Compliance with Arms Control Agreements, for verifiability assessments for all international arms control and nonproliferation agreements, and for specialized compliance reports required by U.S. Senate Resolutions of ratification, such as the condition 10(c) report on the Chemical Weapons Convention.