Recent research presented in American Antiquity (66:36-46) proposed that the prehistoric Puebloan communities of Chaco Canyon in the American Southwest conformed to a matrilocal pattern of postmarital residence. The inference of matrilocality at Chaco Canyon was based on the assumption that a number of the most likely modern descendants of the Chacoans are matrilocal, including the present-day Zuni and Hopi Indians, and that the household floor area had increased to a level indicative of female-based residence. The present study assesses these two important assumptions using biological and architectural data. Our results indicate the assumptions needed to infer matrilocal residence at Chaco Canyon might not be satisfied. The biological evidence indicates close relationships with both matrilocal and bilocal present-day populations, while the architectural evidence is more consistent with a male-based pattern of postmarital residence. Limitations to the study of postmarital residence at archaeological sites are discussed.