The chief goal of this book is to illustrate and establish that language use, particularly the effect of frequency, plays an important role in the determination of phonological form and representation. It might seem that there could be little question about this proposition inasmuch as language is indeed produced and used (exclusively) by human beings, who are subject to myriad social and pragmatic forces in addition to performance variations, but the practice of modern generative and even earlier structural phonology has been to look aside from these functional considerations and to focus instead on static patterns of distribution (structuralism) or dynamic operations of substitution (generative phonology). Bybee seeks to show that how language is used does matter to the phonology, as it does to other aspects of grammar, and I think the volume succeeds in calling attention to this understanding. But on the analytical level, a number of phonological babies get thrown out with the structuralist bathwater, though, as will be highlighted below, it is hardly necessary for a functionally informed phonology to lose its formal rigor or to abandon insights into the patterning of sounds.The book is organized into eight chapters. Chapter 1, "Language Use as Part of Linguistic Theory," lays out the background of recent usage-based theorizing about language and identifies many of the relevant studies carried out under models of connectionism, natural categorization, and emergent structure. The role of frequency, both token and type, in facilitating sound change is also underscored (more frequent tokens change first, more frequent types remain productive), but a point of view is also assumed in which language change, through language use, becomes the explanation, seemingly, for everything:Thus, functional constraints are manifested in specific languages through individual acts of language use. If there is a constraint comparable to the NO CODA constraint of Optimality Theory, it is a result of the phonetic tendency