How much of language is motivated? Recently, cognitive and functional linguists have proposed new solutions to this intriguing question. The thirteen articles collected in this volume cover various aspects of motivation in grammar and in the lexicon. The phenomena discussed in the contributions can be grouped into four types of motivation, which, along with other types, are explicated in the introductory chapter: ecological motivation, i.e. motivation of a linguistic unit due to its place, or "ecological niche," within a system; genetic motivation, i.e. motivation of present-day linguistic...