We are currently living through a period of substantial political uncertainty, and many of us are facing an unquantifiable risk of terrorist action, but would however have to deal with the consequences of any such action. Terrorists have demonstrated a sophisticated ability to produce high mortality "spectaculars", thus far with conventional weaponry. We are advised that we face challenges from non-conventional weaponry such as the deliberate release of chemical, biological or nuclear material. However, given recent intelligence and political failure, the confidence that we can place on such advice is uncertain. Several factors do however seem clear: for many of us the risks of attack have unequivocally increased; our previous major incident plans were designed for an out of date paradigm, and need revising; and the revision of our plans provide us with the opportunity for a thorough review of how we would deal with man-made or natural disasters. Health care systems are now very complex, and when events render such complexity impossible, we need to be sure that we can function with externally imposed simplicity.