Some observers believe that plutonium reprocessing is on the verge of an expansion—while others argue that the end of the practice is in sight. The risk of nuclear proliferation has always been the chief objection to reprocessing, but proponents argue that today, with uranium enrichment technology more easily available, reprocessing no longer represents an efficient route toward nuclear weapons. Supporters also tout the energy security that reprocessing could provide to nations without indigenous uranium sources and the reductions in high-level nuclear waste that reprocessing might achieve. Opponents counter that reprocessing offers only marginal benefits in waste reduction and in any event makes little economic sense. Taking into account issues ranging from proliferation to nuclear waste to cost, how should nations approach plutonium reprocessing?