Stephanie L. Possehl

Director, Space and Missile Defense

Ms. Stephanie Possehl is the Director for Space and Missile Defense, supporting the Deputy Assistant Secretary of Defense for Strategic, Space, and Intelligence Portfolio Management (SSIPM), within the Office of the Under Secretary of Defense for Acquisition and Sustainment (OUSD(A&S)). She leads assessments of cost, schedule, and performance risks and provides guidance and recommendations on more than $9 billion in acquisition portfolios and programs.

Most recently, Ms. Possehl was the Principal Deputy Director for Systems Engineering and Architecture within the OUSD for Research and Engineering (OUSD(R&E)). She produced engineering and test and evaluation (T&E) policy, guidance, and standards, and led communities dedicated to advancing the engineering practice in various disciplines such as systems engineering, digital engineering, reliability and maintainability, modeling and simulation, software, manufacturing and quality, human systems integration, and modular open systems approach. She was the functional area leader for the Engineering and Technical Management (ETM) and T&E acquisition workforces. She also supported Major Defense Acquisition Programs through engineering assessments and initiated development of a Systems of Systems architecture capability within OUSD(R&E). She was previously the Acting Deputy Director for Engineering, serving as the Department of Defense’s Chief Engineer for Advanced Capabilities and leading Mission Integration; Engineering Policy and Systems; Developmental Test, Evaluation, and Assessment; the Joint Hypersonics Transition Office; and the Strategic Intelligence Analysis Cell.

Prior to joining OSD, Ms. Possehl supported the Missile Defense Agency in positions including Deputy Program Manager for Aegis Ballistic Missile Defense (BMD) Weapons Systems and Program Manager for Sea-Based Terminal. She oversaw all aspects of technical, financial, and acquisition efforts for these ACAT I-equivalent programs that developed, delivered, and sustained critical BMD capability for the U.S. Navy. She also served as the acting Deputy Program Executive, sharing responsibility for leading the Aegis BMD portfolio of programs totaling approximately $2 billion per year.

Ms. Possehl has more than 25 years of Federal service with the DoD, beginning her career as a GS-01 Step 01 engineering intern. Her previous positions include teaching senior-level program management and systems engineering at the Defense Acquisition University and providing engineering and project management support to the U.S. Navy STANDARD Missile Program Office and the Naval Surface Warfare Center/Dahlgren Division.

Ms. Possehl holds a Mechanical Engineering and an Technology Management, both from the University of Maryland, and has completed doctoral-level coursework in engineering and technology management at Northcentral University. She is a member of the Acquisition Professional Community and is DAWIA Level 3 certified in Program Management and Engineering. She received the MDA Medal for Exceptional Civilian Service (2020), Navy Superior Civilian Service Award (2018), and Navy Meritorious Civilian Service Award (2015).