Jill de Villiers has authored and edited three books about language acquisition and numerous chapters and journal articles, most of them on the acquisition of complex syntax in preschoolers. She is now studying the impact of language acquisition on cognitive development, particularly on theory of mind. In addition to the development of new diagnostic tests for language assessment, she consults on designing computer software for language intervention.

Dr. de Villiers received her BSc in Psychology from Reading University in England in 1969 and then a Ph.D in Experimental Psychology from Harvard University in 1974, where she worked with Professor Roger Brown on language acquisition. She then taught at Harvard as an Assistant Professor of Psychology from 1974 to 1979. In 1979 she took a position jointly in the Psychology and Philosophy departments at Smith College, where she is now the Sophia and Austin Smith Professor.