What evidence is sufficient to justify the release of a computer-based safety critical system? How should this evidence be presented to certification bodies or regulatory authorities? What best practices should be applied? These are just a few of the questions addressed by Justifying the Dependability of Computer-based Systems, which provides a framework for the justification of the dependability of a computer-based system. The book also explores some of the more fundamental aspects of safety evaluation, such as the nature of models, arguments, evidence and documentation, and the ways to deal with different types of risk and uncertainty. Justifying the Dependability of Computer-based Systems will be of value to software, computer system, instrumentation and control engineers, and regulators working in industry sectors such as nuclear safety. Pierre-Jacques Courtois is a Professor in the Department of Computer Science and Engineering at the Catholic University of Louvain-la-Neuve, with particular research interests in safety-critical software for the nuclear industry. He has more than fifteen years experience in the nuclear safety industry, having worked as a nuclear safety advisor in Finland and the UK, and as a consultant to the International Atomic Energy Agency (IAEA) and the Organisation for Economic Co-operation and Development (OECD).