Plutonium is a man-made material that can be used for both energy production and nuclear weapons. The global plutonium stockpile, created by both nuclear disarmament and civilian plutonium programs, can be a serious threat to the international nuclear non-proliferation regime. Those who see plutonium as invaluable energy source, such as Japan, would like to preserve the plutonium technology option for energy security reasons. Is there a way for those countries to do so without adding to non-proliferation concerns? This proposed project is intended to clarify the conditions necessary to maintain a technology option, and to suggest realistic choices for civilian plutonium programs while minimizing the proliferation risks associated with plutonium use.