Zaenen obtained her Ph.D. at Harvard University with her doctoral thesis Extraction Rules in Icelandic in 1980. After a post doc at M.I.T. she taught syntax at the University of Pennsylvania, Harvard and Cornell University before joining PARC and Stanford. During the 90s, she was the manager of the Natural Language group of the Xerox Research Centre Europe in Grenoble, France. Zaenen retired from PARC in 2011. She has worked on both the syntax of Germanic languages and on the development of Lexical Functional Grammar (LFG), with excursions into lexical semantics. Her contributions to the theory of Lexical Functional Grammar are in the development of notions such as long-distance dependencies, functional uncertainty and the difference between subsumption and equality. She has had 27 scientific publications between 1996 and 2008,. Zaenen is also known for her sharp commentary on research trends in Computational Linguistics. Currently she is a member of a research group on Language and Natural Reasoning at CSLI working on the linguistic encoding of temporal and spatial information, local textual inferences and natural logic. In 2013 Zaenen was honored by a festschrift edited by Tracy Holloway King and Valeria de Paiva.