This 4th Edition, SI Version, retains the style and presentation of all previous editions. As ever, theory is reinforced through application to a wealth of engineering problems. These problems are varied and relevant to the real world, and have been extensively revised: 50 per cent of them are new for this edition. The emphasis is very much on the practice of engineering design, making many problems open-ended. The problem sets have been graded into introductory and representative, with more challenging problems located at the end of the problem sets. Computer-orientated problems, involving the finding of a condition of design or criticality, are also given, as are example problems complete with hints and suggestions.