'When David R. Olson asked his apparently pre-verbal 1-year-old to get her shoes, she promptly complied - much to his surprise. That incident planted the seed for a deep enquiry. Had she truly understood him? What does it mean to ascribe understanding to such a young child? We also need to consider who is doing the ascribing. Are young children able to ascribe understanding to themselves? And what about animals and computers? Drawing on the contributions of philosophers, linguists, and psychologists, David R. Olson proposes that understanding is a uniquely human capacity, slowly acquired as part of a web of language practices. His book is a provocative and original contribution to the study of children's theory of mind.' Paul Lansley Harris, Harvard Graduate School of Education, USA