In one of the most thorough studies ever prepared of a California language, Hill's grammar reviews the phonology, morphology, syntax and discourse features of Cupeno, a Uto-Aztecan (takic) language of California. Cupeno exhibits many unusual typological features, including split ergativity, that require linguists to revise our understanding of the development of the Uto-Aztecan family of languages in historical and areal perspective.