This project addresses the question of how children arrive at the intuitions adults have about the relative acceptability of complex words. It aims to do so by systematic exploration of various characteristics of word-formation processes (e.g., phonological, semantic, etymological, frequency, blocking) that might be significant in the child's lexical induction. The primary methodologies will be use of sentence completion, compound formation, lexical decision, and picture matching. Much of research to date on lexical acquisition focuses on when children acquire word-formation rules such as compounding and affixation, but it is as yet unclear how such processes fit into the developing structure of the lexicon itself. The data from this project, evaluated within the framework of current linguistic models of lexical structure, will provide a unified account of a variety of word-formation processes and suggest ways in which structure might develop within the child's lexicon.