Why do people gesture while speaking? What role does this activity play in verbal exchanges? Which kind of relationship does it exhibit between the verbal and the gestural domains? This book attempts to answer these questions by surveying research on gestures done from various perspectives: psycho- and sociolinguistics, ethology, social, cognitive, and developmental psychology, and neuropsychology. This large coverage makes it unique in the field. Furthermore, the delineation of several approaches to the topic yields a clearer picture of their respective contributions than a commitment to a single view.