Mr. Sean O'Keefe was sworn in as the Deputy Under Secretary of War for Personnel and Readiness on September 25, 2025. In this role, Mr. O'Keefe serves as the primary assistant to the Under Secretary on force readiness; force management; health affairs; National Guard and Reserve Component affairs; education and training; and military and civilian personnel requirements and management, including quality of life matters.

Most recently, Mr. O'Keefe served as a professional staff member for the Senate Armed Services Committee (SASC), where he was responsible for a significant portfolio focused on Personnel and Readiness issues, including military and civilian personnel policy, military end strength, compensation, the Military Health System, and National Guard and Reserve Component affairs. Prior to his time with the SASC, Mr. O'Keefe worked as a senior policy analyst at the Bipartisan Policy Center (BPC), where he was the principal staff lead for a commission focused on modernizing military personnel policies. Before joining the BPC, Mr. O'Keefe served as an active-duty financial management officer in the U.S. Air Force.

Mr. O'Keefe is a graduate of the U.S. Air Force Academy and earned a master's degree from The George Washington University. He is the author of numerous reports on military and civilian personnel policy, military health care, military families, readiness, and compensation.