Each of the 21 chapters in this volume reflects a view of language as a dynamic phenomenon with emergent structure, and in each, gesture is approached as part of language, not an adjunct to it. In this, all of the authors have been influenced by David McNeill's methods for studying natural discourse and by his theory of the human capacity for language. The introductory chapter by Adam Kendon contextualizes McNeill's research paradigm within a history of earlier gesture studies. Chapters in the first section, Language and Cognition, emphasize what McNeill refers to as the intrapersonal plane. Many of the chapters adduce evidence for McNeill's claim that gestures can serve as a window onto the speaker's mind. Chapters in the second section, Environmental Context and Sociality, emphasize the interpersonal plane and exemplify McNeill's focus on how moment-to-moment language use is determined by contextual factors. The final section of the volume, Atypical Minds and Bodies, concerns lessons to be learned from studies of aphasic patients, autistic children, and artificial humans.