In recent decades solid state physics has seen many dramatic new developments and has become one of the largest independent branches of physics. It has simultaneously ex panded into many new areas, playing a vital role in fields that were once the domain of the engineering and chemical sciences. A consequence of this explosive development is that no single university lecturer can today be expected to have a detailed knowledge of all aspects of this vast subject; likewise, it is impossible to conceive of a course that could offer students a comprehensive understanding of the entire discipline and its many applications. In view of this situation, it is particularly valuable to have a textbook that gives a concise account of the essential elements of the physics of solids. In this book the fun damental aspects of solid state physics are presented according to the scheme: Chemical bonding, structure, lattice dynamics, and electronic properties. We believe that this se quence is the optimum choice for tutorial purposes. It enables the more difficult con cepts to be introduced at a point where a basic understanding of fundamental ideas has already been achieved through the study of simple models and examples. In addition to this carefully structured exposition of classical solid state theory based on the periodic solid and the one-electron approximation, the book also includes comprehen sive descriptions of the most active areas in modern research: Magnetism, superconduc tivity and semiconductor physics.