Within the Dept. of Energy (DoE), the National Nuclear Security Administration's Office of Defense Programs is responsible for the national nuclear weapons stockpile. This report addresses DoE's management of its National Nuclear Security Administration's Stockpile Stewardship Program. Specifically, it discusses the Administration's approach to the program's (1) planning, (2) new budget structure, and (3) organizational and leadership structure. In addition, it assesses the program's experience with extending the life of nuclear weapons in the stockpile and the management processes used for overseeing life extensions.