The Fission and Fusion Systems program engages in designing and analyzing advanced nuclear reactor systems for a wide variety of applications.

The Fusion Safety Program focuses on the technology of fusion reactor materials, plasma and tritium interactions and characterization and transport of dust. This work is performed in support of the Department of Energy (DOE) Office of Science national fusion energy program and the International Thermonuclear Experimental Reactor (ITER).

The other major focus of the department is analytical support and design of Generation IV reactor systems and power conversion. Emphasis is on integrated design activities (reactor physics, thermal fluids and energy conversion) with the major customer being the DOE Office of Nuclear Energy, Science and Technology. Current research and development is in Very High Temperature Reactor design, nuclear hydrogen production and fast reactor transmutation of spent fuel.