The book offers a sound, easily readable theoretical background for dependability prediction and analysis of engineering systems. The book bridges the gap between the real life dependability problems and very sophisticated and highly specialized books in this field. It is addressed to a broad readership including practicing engineers, reliability analysts and postgraduate students of engineering faculties. The professionals in the field may also find some new material that is not covered in available textbooks such as fuzzy logic evaluation of dependability performance, uncertainty assessment, open loop sequential analysis of discrete state stochastic processes, approximate solving of Markov systems.