Nuclear emergency planning and management profoundly depend on computer-aided decision support tools that gather and analyze data on radioactive emissions, meteorology, demography, geography, etc., and provide decision support for prevention/mitigation, response, and recovery. The discussion primarily focuses on issues related to the behavioral and decision-making processes of the various players in the evacuation system, logistics, the generation of realistic scenarios for testing contingency plans, the validation of such decision support tools, and future trends in technology and the emergency planning and management process.