xxxix, 729 p. : ill. (some col.) / Kurtop is a Tibeto-Burman language spoken by approximately 15,000 people in Northeastern Bhutan. This dissertation is the first descriptive grammar of the language, based on extensive fieldwork and community-driven language documentation in Bhutan. When possible, analyses are presented in typological and historical/comparative perspectives and illustrated with ample data, drawn mainly from texts but also elicitation as need be. Within Tibeto-Burman, Kurtop has been placed within the East Bodish sub-branch. Data presented in this study support this placement and confirm previous observations that the East Bodish languages are close relatives, but not direct descendants of Classical Tibetan. The link between the current East Bodish languages and Bhutanese prehistory remains unclear but the Kurtop grammar is a first step at understanding the historical relations. The most remarkable aspect of Kurtop phonology is the tonal system, which is contrastive following the sonorants, but incipient following the obstruents, except the palatal fricative, for which tone has completely replaced a previous contrast in voicing. Tone is present only on the first syllable of stems, where vowels are also slightly longer. Kurtop is agglutinating and polysynthetic. Words generally consist of two or three syllables, but may be as long as five or six, depending mainly on suffixing morphology. Like most languages of South Asia, Kurtop exhibits verb-final syntax and the typological correlations that follow, including postposition (or relator noun constructions), auxiliaries after the verb, and sentence-final particles. The case marking system is 'pragmatic' ergative, where an ergative marker is required in some transitive contexts, but not in others. In other contexts, including for some intransitive verbs, the ergative signals a variety of pragmatic or semantic factors. This ergative system, though typologically unusual, is characteristic of many Tibeto-Burman languages, including neighboring Dzongkha and Tshangla. Nominalization and clause-chaining are two essential components of Kurtop syntax, constituting a majority of clauses and a diachronic source for much of the main clause grammar. The evidential/mirative system in Kurtop is also of typological interest, encoding a wide range of values pertaining to speaker expectation as well as mirativity and source of knowledge. / Committee in charge: Scott DeLancey, Chairperson and Advisor; Spike Gildea, Member; Doris Payne, Member; Gyoung-Ah Lee, Member; William Ayres, Outside Member