Acquisition and the lexicon collects revised versions of nineteen primary papers and four commentaries presented at the 5th Conference on Laboratory Phonology, held at Northwestern University in July 1996. It is not possible to do justice to each paper in a collection this large and diverse, so individual papers will be discussed as they relate to three themes that emerge from the book as a whole: (i) the relationship between phonology and speech processing – this volume contains more papers on speech processing than its predecessors in the Laboratory Phonology series, which brings to the forefront questions about the relationship between phonological theory and theories of speech processing; (ii) the phonetics–phonology divide – a number of the phonology papers question the common assumption that phonetics and phonology are separate components of grammar; (iii) frequency effects – results are presented showing effects of the frequency of words and other phonological units in a striking variety of domains.