This book fulfills the need for a short, modern, introductory text on linear elastic fracture mechanics and its engineering applications. Suitable for use by engineering undergraduates, and other newcomers to the subject, it:- • Explains the main ideas underlying present day linear elastic fracture mechanics and how these have been developed. • Shows how the ideas can be used to carry out calculations answering the question 'Does this crack matter?' from the viewpoint of an engineering designer. • Provides an understanding of the basis of standard methods and software employed to carry out calculations. • Includes additional, more advanced material, where this will increase understanding of the sometimes formidable mathematics involved, and of the various simplifications and approximations used in practical applications. The author includes all the material central to an undergraduate introductory course and ends each chapter with an overview of the material covered to aid accessibility. Familiarity with the mechanical properties of metallic materials, and with the linear elastic stress analysis of uncracked bodies is assumed.