South Korea's reliance on nuclear energy has brought about one very negative consequence: an accumulation of spent nuclear fuel. This study examines pyroprocessing and the development of safe and comprehensive ways of dealing with spent fuel. It concludes that, even under the most optimistic scenario, pyroprocessing and the associated fast reactors will not be available options for dealing with South Korea's spent fuel on a large scale for several decades. Seoul will need to find other options, most urgently for managing spent fuel in the short- to medium-term, as well as permanently, to cope with the proper management of its spent fuel or the high-level waste that will remain after pyroprocessing.