The office of Systems Engineering and Architecture (SE&A) applies engineering expertise to achieve system-of-systems capabilities and advance engineering practice within the Department of Defense.

Mr. Thomas Simms poses for his official portrait in the Army portrait studio at the Pentagon in Arlington, Va., Jan. 24, 2023.  (U.S. Army photo by William Pratt)

Mr. Thomas W. Simms

Acting Principal Deputy Director, SE&A

Mr. Thomas Simms is the acting Principal Deputy Director for the DoD office of Systems Engineering and Architecture. He leads the effort to advance the engineering practice within the DoD to include systems engineering, software engineering, digital engineering, and specialty engineering areas such as reliability, manufacturing, and human systems integration.

Engineering Foundations

Engineering Foundations develops and promotes the use of innovative and modern engineering principles and techniques to advance engineering practice within the DoD.

The Engineering Foundations team provides policy, guidance, standards, and best practice resources; facilitates communities of practice; and develops the defense engineering workforce by defining competency models and curricula.

close-up of interconnected points

Engineering Foundations includes the following areas:

Systems Engineering

Specialty Engineering

Digital Engineering, Modeling and Simulation

Software Engineering

Defense Standardization Program

Engineering Applications

Engineering Applications applies engineering expertise to inform risk‐based decisions and develop system-of-systems architectures to reduce integration risk for mission‐enabling systems.

This team provides engineering assessments and architectures.

Engineering Applications focuses on processes, products, customers, and interactions and dependencies among organizations.

The team works to define system context, boundaries in interfaces and interactions, key data elements, and key data conversions to facilitate data sharing, communications, and decision making.


Send an email to SE&A.


Office of the Under Secretary of Defense,
Research and Engineering (USD(R&E))
The Pentagon, Washington, DC 20301