Section headings and selected papers. Timing Aspects. Towards a common safety description model, R E Bloomfield et al. The formalization and analysis of a communications protocol, G Bruns & S Anderson. Applications. Improving software quality in a space application, A Pasquini. A software tool for fault-tolerant systems in the operational phase, K Sismail. Hardware. Applying programmable gate arrays to provide diversity in safety relevant systems, W A Halang & J M Schut. Some answers to the problem of safety in microprocessor-based devices, J Ph Gerardin et al. Assessment I. Using fault tree analysis in developing reliable software, E O Ovstedal. Synchronized local state diagram: a modelling methodology under development, P E Heegaard et al. Assessment II. Balancing reliability requirements for field devices and control logic modules in safety systems, L Bodsberg & P Hokstad. Classification of critical events in systems described by Grafcet using the Markov process, Z Abazi & T Peter. Specification and Development. An early warning method for safety-critical software development, A D Pengelly. A configuration management system for incremental delivery projects, F Redmill. Security. Security evaluation criteria, S J Knapskog. Information security issues in transaction systems applied to an integrated road traffic environment, B G Andersen. Verification and Validation. Software safety checks using stored tested paths, G Dahll. Models. Systematic software testing strategies as explanatory variables of proportional hazards, F Saglietti. The balancing of quality assurance against validation activities, T Stalhane. Author index. Keyword index.<br>