This volume represents the second of our occasional departures from the format of an annual review series, being devoted to one coherent topic. We have the pleasure therefore in presenting a concerted sequence of articles on the use of Simulators for Nuclear Power. An essential attribute of a quantified engineer in any discipline is to be able to model and predict, i.e. to analyze, the behaviour of the subject under scrutiny. Simulation goes, one would argue, a step further. The engineer providing a simulator takes a broader view of the system studied and makes the analysis available to a...