Sierra or Western Mono (a.k.a. Monache) is a Native California Indian language spoken in central California along the western foothills of the Sierra Nevada Mountains. It is a member of the Numic branch of Uto-Aztecan languages, and is closely related to Owens Valley Paiute, Mono Lake Paiute and the other languages on the eastern side of the Sierras and in the Great Basin. Taaqwa Nüümümaa Yaduhanaamat! “Let’s Speak Sierra Mono” is the first complete textbook of the language, written for complete beginners with no previous knowledge of the language or linguistics. It is designed to be used without a teacher, introducing the language simply and methodically. Each lesson contains clearly written explanations of Mono grammar with copious examples, exercises for students to practice their language skills, conversations to give students a sense of conversational Mono, and a vocabulary of all the words introduced in that lesson. The lessons contain all the grammatical features of the language, making it useful to linguists and others with a professional interest in the Mono language. The book also contains a complete Mono story written by fluent speaker Rosalie Bethel (of North Fork), which is fully analyzed, information on traditional Mono culture, and suggestions on how to continue one’s study of Mono, whether one is a community language activist or just an interested student of the language. There is also a Mono-English glossary at the end of the book. The author, an emeritus professor of linguistic anthropology and American Indian Studies at Idaho State University, began documenting the language with the late Rosalie Bethel in 1979, and has co-authored two Mono dictionaries, as well as other articles on Mono language, music and mythology.