This book focuses on a recent, important psychological theory of autism, the 'theory of mind' hypothesis. This claims that children with autism fail to develop the ability to think about mental states in the normal way, and thus fail to understand behavior in terms of mental states. In current terminology, they are impaired in the development of a 'theory of mind'. This psychological deficit is held to underlie some of the key feature of the syndrome: the abnormalities in social and communication development. The editors have collected together both the evidence and the controversies surrounding the theory, and present these as a valuable debate about the nature of what is widely recognized as the most severe childhood psychiatric disorder. The chapters are written by scholars from a variety of disciplines (developmental psychology, neuropsychology, philosophy, psycholinguistics, primatology, child psychiatry, and psychoanalysis). The book stands as an illustration of the mutual influence of studies of the mind from the prespectives of normality and pathology.