Gestures are prevalent in communication and tightly linked to language and speech. As such they can shed important light on issues of language development across the lifespan. This volume brings together studies from different disciplines that examine language development in children and adults from varying perspectives. It provides a review of common theoretical and empirical themes, and the contributions address topics such as gesture use in prelinguistic infants, the relationship between gestures and lexical development in typically and atypically developing children and in second language learners, what gestures reveal about discourse, and how all languages that adult second language speakers know can influence each other.