The world of operational police command is a challenging and complex one, where significant command decisions need to be made amid uncertainty and within narrowing time-frames. The consequences attached to these decisions can often be far reaching and have been in some cases grave, as in the case of disasters such as those at Bradford and Hillsborough football stadia. Accordingly, there is a pressing need to instil within key command officers, the skills and the experience necessary to make these bold and effective command decisions, but within an environment where such dire Consequences (as those that follow a disaster) do not arise from mistakes or inadequacy. The question then becomes how to create such an environment which is at the same time both safe and sufficiently realistic to provoke similar decisional reactions to those that would occur at a real event. Even if this was achievable a further stage would be necessary in which such learning came to be transferred back into an operational command situation. This thesis explores in a systemic way the design, implementation, testing, modification and re-testing of a critical incident management command simulator whose central tenet was to create an immersive simulation that, by virtue of its high degree of fidelity, was capable of engendering experience of the management of critical incidents for a target population comprising senior police command officers. From tentative beginnings to its operational installation as a fully functional command training simulator, this thesis maps out the key development decisions which were informed by the findings of a series of trials, observations, interviews, surveys and physiological measurements. At the same time, it describes the theoretical models used to explain the relationships between and functionality of the system and its individual components, whilst exploring the dimension of human computer interaction. This is action research in that the findings it generated led to an incremental series of modifications to what became an operational training simulator (named MINERVA) on which useful and transferable command training actually took place.