Anna Papafragou is a Professor in the Department of Linguistics at the University of Pennsylvania and the director of the University's interdisciplinary graduate program in Language and Communication Sciences. Her research focuses on how children acquire meaning in language, how language is used and understood, and how language interfaces with human perception and cognition. She is an elected Fellow of the Association for Psychological Science and serves on the Governing Board of the Cognitive Science Society. John C. Trueswell is a Professor in the Department of Psychology at the University of Pennsylvania and the co-director of the University's MindCORE initiative in Integrative Language Science and Technology. His research focuses on understanding how children develop the ability to process language in real-time, and how this ability interacts with the acquisition of language. He is an elected fellow of the Association for Psychological Science, the American Association for the Advancement of Science, and the Cognitive Science Society. Lila R. Gleitman is a Professor Emerita of Psychology and (by secondary appointment) Linguistics at the University of Pennsylvania. She has conducted foundational work on language acquisition, and the relationship between language and other cognitive systems. She is an elected member of the National Academy of Sciences, an elected fellow of the American Association for the Advancement of Science, a Fyssen Foundation Laureate, and a winner of the Rumelhart Prize from the Cognitive Science Society.