This leaflet, which is in the form of a fold-up chart, has panels of text which summarize the emergencies that could arise and the countermeasures and emergency plans that have been prepared should nuclear accident occur or affect the United Kingdom. The levels of radiation doses at which various measures would be introduced are outlined. The detection and monitoring programmes that would operate is illustrated. The role of NRPB and the responsible government departments are set out together with an explanation of how the National Arrangements for Incidents involving Radioactivity would be coordinated. (UK).