Language isolates provide unique insights into human history and linguistic diversity. Nevertheless, isolates have been studied less exhaustively than non-isolates. The eleven papers gathered in this volume provide new methodological tools in order to better understand isolates, including a detailed, in-depth, up-to-date discussion of what it means to be a language isolate and the criteria by which languages should be classified as isolate. The book also provides a series of techniques, some refined on the basis of former literature, and others new, in order to recover the histories of language isolates. In addition, the papers in this volume advance our knowledge about each of the individual languages studied here, which are, for the most part, endangered and under-documented. This book will appeal to a broad audience spanning typologists, historical linguists, descriptive linguists, and teachers of linguistics.