Evelyn Hatch is Professor Emerita in the UCLA Department of TESL/Applied Linguistics, where she did most of her career. She trained across fields — BA political science, MA linguistics, PhD education — and that breadth shows in the way her work reframed SLA in the 1970s.
Before Hatch, second-language research was largely an inventory of learner errors at the sentence level. Her 1978 paper "Discourse analysis, speech acts, and second language acquisition" and the 1978 edited volume Second Language Acquisition turned the field's attention to interaction: learners do not acquire syntax and then deploy it in conversation, they build syntax out of conversation. That move is the hinge on which the Interaction Hypothesis swings a decade later, and its fingerprints are on every subsequent framework that takes classroom talk seriously.