Creek is a member of the Muskogean language family with some 4,000, mostly elderly speakers residing in three communities: the Muscogee (Creek) Nation of eastcentral Oklahoma, the Seminole Nation of central Oklahoma, and the Brighton Reservation within the Seminole Tribe of Florida. This project seeks to document these three dialects by expanding an existing corpus of Creek texts and by using the corpus to create the first modern reference grammar of the language. The resulting textbase will allow researchers to perform linguistic analysis and read transcriptions or translations of documents. The reference grammar will provide information on the phonetics, phonology, morphology, and syntax of the language while paying special attention to matters of theoretical interest to linguists, including the description of stress, tone, syllable structure, 'active' agreement, switch reference, grammatical relations, voice, directionals, and external possession. The resulting materials will contribute to comparative and historical studies of Muskogean languages, to theoretical work in linguistics, and to community efforts to learn and maintain the language.