The late pre-contact political economies of Hawai'i and Maui Islands were supported in large part by intensified dryland field systems, focused on the cultivation of sweet potatoes. Three such systems have been well documented for Hawai'i Island, and one for Moloka'i Island, but none previously for Maui. We report here the results of remote sensing and GIS analysis, combined with ground survey, of such an intensive field system in Kaupō District, Maui. The field system is archaeologically manifested by a closely spaced grid of east-west trending embankments, delineating small field plots, bisected at right angles by longer north-south trending walls, which primarily appear to be territorial divisions. A range of smaller features such as enclosures, shelters, and platforms are found within the field system area indicating the presence of a complex social community integrated within the system. In aggregate the field system covered between 12.5 and 15 km2, and could readily have supported a population of 8000-10,000 persons. Hawaiian oral traditions indicate that Maui king Kekaulike made Kaupō his seat in the early eighteenth century. Two large temples, Lo'alo'a and Kou, are situated at the east and west extremes of the field system, and further indicate the significance of this highly productive landscape.