Ute is a Uto-Aztecan language of the northernmost (Numic) branch, currently spoken on three reservations in western Colorado and eastern Utah. Like many other native languages of Northern America, Ute is severely endangered. This book is part of the effort toward its preservation. Typologically, Ute offers a cluster of intriguing features, best viewed from the perspective of diachronic change and grammaticalization. The book presents a comprehensive synchronic description of grammatical structures and their communicative functions, as well as a diachronic account of a grammar in the midst of change. The book is the first of a 3-volume series which also includes a collection of oral texts and a dictionary.