This is the first grammar ever written of Lele, an endangered language spoken in the Republic of Chad. The language belongs to the Chadic branch of the Afro-Asiatic family, whose other members are Semitic, Egyptian, Cushitic, Omotic, and Berber. Grammar of Lele explores the use of vowel harmony as a means of coding categories of morphemes. Suffixes undergo vowel harmony rules; clitics do not, and must occur in specified contexts; free morphemes, which also do not undergo vowel harmony rules, have relatively free distribution. The language has also an intriguing reference system, complex sentence structures, and the coding of backgrounding. The study of these and other categories and structures not encountered in the more familiar Indo-European languages will appeal to lovers of languages and linguistics.