This book is concerned with the fundamentals of the acoustic surface wave field, with stress on implications for signal processing. The book includes in one place the following four most important basic aspects of this field: the properties of the basic wave types, the principles of operation of the most important devices and structures, the properties of materials which affect device performance, and the ways by which the devices are fabricated. The attempt throughout has been to stress the the fundamentals so that this book is not likely to be outdated soon. Although a variety of books and journal publications have appeared which present certain basic material or contain broad reviews, there is no single published source, to our knowledge, that duplicates the intent or the contents of this book.