An American Indian language belonging to the Muskogean linguistic family, Koasati is spoken today by fewer than five hundred people living in southwestern Louisiana and on the Alabama-Coushatta Indian Reservation in Texas. Geoffrey D. Kimball has collected material from the speakers of the larger Louisiana community to produce the first comprehensive description of Koasati. The book opens with a brief history of the Koasati. The chapters that follow describe Koasati phonology, verb conjugation classes and inflectional morphology, verb derivation, noun inflectional and derivational morphology, grammatical particles, and syntax and semantics. A discussion of Koasati speech styles illustrated with texts concludes the book. Because examples of grammatical construction are drawn from native speakers in naturally occurring discourse, they authoritatively document aspects of a language that is little known.