Much research has recently been devoted to the study of the development of a representational theory of mind. By about age 4 most children understand that people, including they themselves, may misrepresent the world (e.g., Flavell, Flavell, & Green, 1983; Gopnik & Astington, 1988;Moore, Pure, & Furrow, 1990; Perrier, Leekam, & Wimmer, 1987;Wimmer & Perrier, 1983). This understanding of false belief is evidence for a representational theory of mind, because it implies an understanding that mental states are attitudes to representations of the world, rather than attitudes to direct copies of reality (Dennett, 1978;Wimmer & Perrier, 1983). Although some research suggests that even 3-year-old children may be able to pass simpler versions of classic theory-of-mind tasks (Chandler & Hala, 1994;Saltmarsh, Mitchell, & Robinson, 1995;Sullivan & Winner, 1993) and may have an implicit understanding of belief (Clements & Perrier, 1994, many researchers maintain the traditional view that fundamental cognitive changes are responsible for 4-year-olds' understanding of false beliefs (e.g., Flavell, 1993;Olson, 1993;Perner, 1995). This research was supported by a Telecom New Zealand research grant to Claire M. Fletcher-Flinn.We thank the children, parents, and teachers of the participating kindergartens. We are grateful to Linda Harris for her assistance in testing the children. We appreciate the thoughtful comments by Michael Corballis and Thomas Keenan on an earlier version of this manuscript.The participating children were a subset of a larger study on the effects of computers on young children. The falsebelief data is expected to be published also in the context of this computer project.Manuscript