The contributions to this book are the invited papers presented at the fifth annual Safety-critical Systems Symposium. They cover a broad spectrum of issues affecting safety, from a philosophical appraisal to technology transfer, from requirements analysis to assessment, from formal methods to artificial intelligence and psychological aspects. They touch on a number of industry sectors, but are restricted to none, for the essence of the event is the transfer of lessons and technologies between sectors. All address practical issues and of fer useful information and advice. Contributions from industrial authors provide evidence of both safety con sciousness and safety professionalism in industry. Smith's on safety analysis in air traffic control and Rivett's on assessment in the automotive industry are informative on current practice; Frith's thoughtful paper on artificial intelli gence in safety-critical systems reflects an understanding of questions which need to be resolved; Tomlinson's, Alvery's and Canning's papers report on collaborative projects, the first on results which emphasise the importance of human factors in system development, the second on the development and trial of a comprehensive tool set, and the third on experience in achieving tech nology transfer - something which is crucial to increasing safety.
