Cottam and Tilley provide an introduction to the properties of wave-like excitations associated with surfaces and interfaces. The emphasis is on acoustic, optic and magnetic excitations, and, apart from one section on liquid surfaces, the text concentrates on solids. The important topic of superlattices is also discussed, in which the different kinds of excitation are considered from a unified point of view. Throughout the book the authors are careful to relate theory and experiment and all of the most important experimental techniques are described. The theoretical treatment assumes only a knowledge of undergraduate physics, except for Green function methods that are used in a few sections; these methods are developed in an appendix. The book also contains extensive references to enable the reader to consult the research and review literature, and problems are provided in each of the main chapters to allow the reader to develop topics presented in the text.