Functional linguistics is concerned with the function of language and considers it an essense of human language. Views like this is not particularly new, but rather traditional in the history of linguistics. But today functional linguistics is constituted by a wide range of theoretical and methodological concerns. What unifies them as functional is the concern with discourse. This is quite natural since language can only function in discourse, not as isolated sentences.This collection of papers reflects some of the major approaches and methodologies in contemporary functional linguistics in Japan and the United States. Based on the fundamental concerns with discourse, the nine articles deal with a variety of up to date topics in functionalism and present numerous analyses, discussing from the question of basic grammatical categories to the inadequacy of some representative analyses in formal linguistics.This book is intended for readers with a wide scope of interest, for example, for those who are interested in discourse and conversational analysis, information structure, modality, aspect, morphology and syntax. Readers will learn how various contemporary functional linguistics is and yet how fundamental the role of discourse is throughout the functional inquiry in language.