In our everyday social lives we routinely understand the behaviour of others by attributing mental states to them. This book draws together from a range of disciplines research into the origins and emergence of this fundamental and astounding ability - the use of a natural theory of mind. In developmental psychology researchers have begun to trace the child's developing understanding of such concepts as others' desires, emotional states and intentions. Ethologists and comparative psychologists have asked how and why an ability to read the mind of another might emerge in the course of evolution. In computer science, the question is how to shape the emergence within computational systems of representations of the minds of others, be it to copy their expertise or to interact with users in a more human fashion. This volume brings together contributions from these three disciplines, with others from philosophy and anthropology, on the central topic of the emergence of theories of mind.