Marquesan is an Eastern Polynesian language whose nearest relations according to present subgrouping theory are Hawaiian and Mangarevan. The literature lists two major dialects referred to as northern and southern although there are dialect differences from island to island and also, to a much lesser degree, from valley to valley on individual islands. While all dialects within the group are mutually intelligible, there are grammatical as well as phonological and lexical differences between the dialects. The data for this study was taken from the Ùa Pou dialect and as such is a partial description of that dialect only. The Ùa Pou dialect of the Marquesan language is spoken on the island of Ùa Pou in Te Henua Ènana (the Marquesas group of islands). The aim of this study is to provide the following: an overview of the work carried out in the field of Polynesian phonology and syntax in the past 30 years; a description of the phonemes and certain suprasegmental features of the sound system of Ùa Pou; and a detailed description of the internal structure of the Ùa Pou phrase.