Because words represent the building blocks upon which the facility to produce and comprehend language at all levels is based, the capacity of a child to learn words has immense impact on his or her developing abilities to communicate and engage properly with the outside world. Both the Keynote Article and the Commentaries in this issue…

Suggests that experimental studies are valuable in analyzing children's language development. Criticizes the scarcity of experimental and naturalistic investigation into preschool language development. Calls for long-term study of continuity and discontinuity in children's school and home learning and between different school stages. Observes that…