This is a survey of current developments in the field of plutonium disposal by the application of advanced nuclear systems, both critical and subcritical. National research and development plans are also summarized. The actinide-fuelled critical reactors are associated with control problems, since they tend to have a small delayed neutron fraction coupled with a small Doppler effect and a positive void coefficient. Current thinking is turning to accelerator-driven subcritical systems for the transmutation of actinides.