The authors, writing with the experience and techlogical background of Electricite de France, an organisation at the forefront of simulation methods, provide a comprehensive and comprehensible treatment of the modelling and simulation techniques currently in use. The text emphasises model design applied to power plants producing energy, generators and motors carrying out energy transformations and networks transmitting energy. The systems are analysed considering each process, from steady state to fast transients, with detailed explanation of the problem to be solved, the choice of models and methods for optimising efficiency. Many examples and references are provided. The book is essential reading for anyone involved in power system engineering, from practising design and development engineers to researchers and postgraduate and advanced graduate students.