All languages change, just as other aspects of human society are constantly changing. This book is an introduction to the concepts and techniques of diachronic linguistics, the study of language change over time. It covers all themajor areas of historical linguistics, presenting concepts in a clear and concise way. Examples are given from a wide range of languages, with special emphasis on the languages of Australia and the Pacific. While the needs of undergraduate students of linguistics have been kept firmly in mind, the book will also be of interest to the general reader seeking to understand langauge and language change. For this fourth edition, a number of new sections have been written, including many new problems and several datasets. Existing materials have been supplemented with new sections on grammaticalization, tonogenesis, morphological change, and using statistical methods in language classification. "Because of the diversity of the data presented and the completeness displayed in these chapters, this book constitutes an essential tool for linguistics students, and for all readers with a smattering in phonetics ... this updated edition shows that the classic work of T. Crowley remains an essential tool both for its completeness and its simplicity, especially thanks to C. Bowern's addition to this new edition." -- Oscar Garcia-Marchena, Lexis The new edition of this popular introductory text on historical linguistics covers all areas of language change, with a focus on Australia and the Pacific. Terry Crowley was Senior Lecturer in Linguistics at the University of Waikato in New Zealand. Claire Bowern is Assistant Professor of Linguistics, Yale University.