Jeremy M. Anglin received his Ph.D. from Harvard University in 1970. He is associate professor of psychology and currently the chair of the Developmental Psychology Division at the University of Waterloo. His research interests include language acquisition and cognitive development. Several of his recent studies have focused on lexical, semantic, and conceptual development during childhood. He has previously been a consulting editor for the Monographs of the Society for Research in Child Development and has served on the editorial board of Child Development. He is the author of The Growth of Word Meaning and of Word, Object, and Conceptual Development and the editor of Beyond the Information Given: Studies in the Psychology of Knowing.George A. Miller received his Ph.D. from Harvard University in 1946. He is a cognitive psychologist at Princeton University. Pamela C. Wakefield received her B.S. from Upsala College in 1982. She is a member of the research staff at Princeton University.

• Abstract vI. Introduction 1II. Estimating Children’s Vocabulary Knowledge 8III. Morphological Development 27IV. Constructing a Basis for Estimating Vocabulary Knowledge 43V. A Study of Vocabulary Development in Elementary School Children 57VI. Distinguishing Potentially Knowable Words from Psychologically Basic Vocabulary 80VII. Vocabulary Development and the Growth of Morphological Knowledge 118Appendix: The 196 Words on Which Children were Tested, with Comments on their Morphological Classifications 153References 157Acknowledgements 166CommentaryOn Anglin’s Analysis of Vocabulary Growth 167George A. Miller and Pamela C. WakefieldReplyKnowing Versus Learning Words 176Jeremy M. AnglinContributors 187Statement of Editorial Policy 188