Spoken on Mavea Island by approximately 32 people, Mavea is an endangered Oceanic language of Vanuatu. This work provides grammatical descriptions of this hitherto undescribed language. Fourteen chapters, containing more than 1,400 examples, cover topics in the phonology and morphosyntax of Mavea, with an emphasis on the latter. Of particular interest are examples of individual speaker variation presented throughout the grammar; the presence of three linguo-labials (still used today by a single speaker) that were unexpectedly found before the rounded vowel /o/; and a chapter on numerals and the counting system, which have long been replaced by Bislama's but are remembered by a handful of speakers. Most of the grammatical descriptions derive from a corpus of texts of various genres (conversations, traditional stories, personal histories, etc.) gathered during the author's fieldwork, conducted for eleven months between 2005 and 2007.