Extensively revised and updated, this new edition of a classic text presents a unified approach to crystallography and to the defects found within crystals. The book combines the classical and exact description of symmetry of a perfect crystal with the possible geometries of the major defects-dislocations, stacking faults, point defects, twins, interfaces and the effects of martensitic transformations. A number of important concepts and exciting new topics have been introduced in this second edition, including piezoelectricity, liquid crystals, nanocrystalline concepts, incommensurate materials and the structure of foamed and amorphous solids. The coverage of quasicrystalline materials has been extended, and the data tables, appendices and references have been fully updated. Reinforcing its unrivalled position as the core text for teaching crystallography and crystal defects, each chapter includes problem sets with brief numerical solutions at the end of the book. Detailed worked solutions, supplementary lecture material and computer programs for crystallographic calculations are provided online (http://booksupport.wiley.com).