[en] This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The original intent of this project was to investigate the possible use of a new fuel form as a means of dispositioning the declared surplus inventory of weapons-grade plutonium. The focus soon changed, however, to managing the larger and rapidly growing inventories of plutonium arising in commercial spent nuclear fuel through implementation of a new fuel form in existing nuclear reactors. LANL embarked on a parallel path effort to study fuel performance using advanced physics codes, while also demonstrating the ability to fabricate a new fuel form using standard processes in LANL's Plutonium Facility. An evolutionary fuel form was also examined which could provide enhanced performance over standard fuel forms, but which could be implemented in a much shorter time frame than a completely new fuel form. Recent efforts have focused on implementation of results into global energy models and development of follow-on funding to continue this research