A longitudinal study of English acquisition by a Vietnamese mother and her daughter is reported. Subjects of this study are Lan, a young Vietnamese woman in her late twenties, and her daughter Than, who was four years old at the time this study began. Neither knew any English when they resettled in Texas in the summer of 1975 after fleeing from Vietnam in the spring of that year. English acquisition began through interaction with the American family sponsors, with whom they continue to maintain close social ties. Vietnamese continues to be the language of the home, but English is developing through the mother's contacts at work and frequent visits with the American sponsors. Than is enrolled in an English-speaking school. A wide range of syntactic structures are examined; the adult acquisition sequencing of the mother is compared with that of her child. Findings have implications for a theory of language acquisition, both first and second, as well as for pedagogical considerations in teaching English as a second language. (Author)