ORA-116 is one of many coastal shell-midden sites in and around Newport Bay, a large, complex wetlands in southern California. Whereas shell-midden studies have traditionally focused on changes in subsistence and settlement patterns, this project took a decidedly different approach. Using a variety of innovative detection measures, eleven structures were identified and excavated. Most were interpreted as house pits; one was inferred to be a sweat lodge. The structures dated between about 300 B.C. and A.D. 700, placing the occupation within the Intermediate period. The archaeological study was augmented by pollen and ostracod analysis of a 1,081-cm core taken from the nearby San Joaquin Marsh, which helped establish the Holocene history of Newport Bay. The authors integrate archaeological, ethnographic, and environmental data in a comprehensive settlement and subsistence model that is sure to be of interest to all scholars of coastal wetlands adaptation.