Yaqui is a Southern Uto-Aztecan language spoken by a people living predominantly in Sonora, with some communities in Arizona. This comprehensive reference on the Sonoran Yaqui language is a descriptive grammar that covers topics on phonology, word classes, verb structure, and complex sentences. John Dedrick, who lived and worked among the Yaquis for more than thirty years, shares his extensive knowledge of the language, while Uto-Aztecan specialist Eugene Casad helps put the material in a comparative perspective. The book includes useful sections on quantifiers and adverbial and deictic particles, often inadequately treated in reference grammars. A section on auxiliary verbs and well-documented information on voice, aspect, and other features of verbal inflection provide readers with useful data for particular lines of linguistic inquiry. Each grammatical point is illustrated by example sentences distinguished by their naturalness and cultural relevance. At the end of the book, a Yaqui text provides a sample of connected sentences in a natural context. Sonora Yaqui Language Structures is a valuable source not only for research on this language family but also for anthropological studies of the Arizona-Sonora cultural region. In addition, it documents an indigenous language for future generations of Yaqui speakers.