Abstract: The NREFS project is re-evaluating the management of radiation accidents, paying attention to environmental, financial and safety issues and to the threat and response phase. In designing our project some two years ago, we were concerned to avoid any assumption that a future accident will be similar to a past accident, in particular the Chernobyl and Fukushima Accidents. After a year of research on the issues to be considered and the criteria that could or should drive the decision making, our concern has increased. We have found that international guidance provided by organisations such as ICRP and IAEA lack the specificity to help decision makers. Precedent set in the handling of earlier accidents provides much clearer and tighter guidance – and, moreover, one may feel that that the public will expect them to follow such precedent. Unfortunately the circumstances of a future accident may make precedent inapplicable. Consequently we believe that there is an urgent need to think more widely about nuclear emergency management.