Alex Fitzsimmons is the Director of the Office of Cybersecurity, Energy Security, and Emergency Response (CESER) at U.S. Department of Energy (DOE). Appointed in May 2025, he leads the Department's efforts to safeguard the nation's energy infrastructure against evolving cyber and physical threats, ensuring resilience and security across critical energy systems.
With more than a decade of experience in energy policy and government leadership, Fitzsimmons has held several key positions within DOE. Most recently, he served as DOE’s Chief of Staff, guiding the Department through its initial 100 days under the Trump Administration. Prior to that, he was Deputy Assistant Secretary in the Office of Energy Efficiency and Renewable Energy (EERE), where he also served as Chief of Staff to the Assistant Secretary. In these roles, Fitzsimmons advanced initiatives related to energy efficiency, advanced manufacturing, and cybersecurity, including the development of EERE’s Cybersecurity Multiyear Program Plan, published in November 2020.
Before rejoining DOE, Fitzsimmons led government affairs at Sila Nanotechnologies, a next-generation energy storage company, and served as Senior Director at ClearPath, focusing on energy storage and critical mineral supply chains. Earlier in his career, he managed policy and public affairs at the Institute for Energy Research and its advocacy arm, the American Energy Alliance.
Fitzsimmons holds a Bachelor of Arts in Political Science from The George Washington University and a Master of Science in Cybersecurity from the Georgia Institute of Technology.