Infants and young children naturally and spontaneously acquire thelexicon of their native language. This accomplishment is a topic ofcentral interest in the cognitive sciences, because it raises core ques-tions in psychology, linguistics, philosophy, computer science, and related Fields. The past several years have witnessed an impressiveaccumulation of new knowledge about the learning of words. Recentdiscoveries in developmental psychology have been especially note-worthy, because they have helped to illuminate a process that isinherently multidimensional and dynamic.

In this edited volume, we invoke the metaphor of weaving to con-sider the acquisition of a lexicon. It has become clear that, to suc-ceed in this task, learners weave together many different threads ofknowledge and skill. These strands include perceptual (visual andauditory) sensitivities, general associative-learning mechanisms, con-ceptual and semantic constraints, an appreciation of lexical formclass, and a rich understanding of communicative intent. It has alsobecome evident that children do not intertwine these strands in auniform fashion over the course of infancy and childhood, resultingin a ?at weave. On the contrary, the evidence reveals much moretexture to the fabric of word learning, with children recruiting someabilities and understandings more heavily at some developmentalpoints than at others.

Like infants and toddlers acquiring their native lexicon, develop-mental psychologists seeking to understand word learning must also become adept at weaving. For the ?eld to progress, researchers mustmove beyond cataloging the isolated strands of knowledge or skill that learners use in any given act of word learning. In particular, ithas become important that we abandon ‘‘either-or’’ approaches, inwhich a single thread is held to explain word learning from infancythroughout childhood. At the same time, we must progress beyond‘‘all-inclusive’’ approaches, in which multiple strands are invoked inways that fail to generate falsi?able hypotheses about lexical devel-opment. We believe that breakthroughs in theories of word learningawait the discovery of precisely which threads of ability or under-standing make which contributions to acquisition at which points dur-ing infancy and childhood.

This volume brings together chapters written by leading scholarsin the ?eld of lexical acquisition. Each contribution focuses directlyon one or more of the various strands of knowledge or skill thatunderpin lexical development in infancy and childhood (e.g., per-ceptual abilities, lexical form class sensitivities, social-pragmaticunderstanding). Although the authors have centered their chaptersprimarily on the results of their own research programs, they havealso considered explicitly how their work ?ts into the emerging pic-ture of lexical acquisition as a multidimensional, dynamic task. As aresult, the volume contains many chapters that explore the interac-tions among multiple threads of skill or knowledge at a speci?c pointin development, and/or the unfolding of children’s reliance on aparticular thread over the course of development.