In order to maintain the long term economic viability of nuclear fuel reprocessing BNFL has a long term ongoing R&D programme into nuclear fuel reprocessing technologies. A major theme of this programme is the use of clean technology to reduce the financial cost of reprocessing, while maintaining the highest standards of safety and environmental care. To ensure reductions in environmental impact in reprocessing do not cause an increase in impact elsewhere in the nuclear fuel cycle, a ’Life Cycle Assessment’ of the fuel cycle is being developed. This life cycle model should allow definition of : (1) the key areas of the cycle responsible or the majority of the environmental impact; (2) the major differences in environmental burden between reprocessing and alternative technologies and (3) the effects any changes in the upstream and downstream processes will have on the entire fuel cycle.