These studies explore the scope of young children's teleological tendency to view entities as 'designed for purposes'. One view ('Selective Teleology') argues that teleology is an innate, basic mode of thinking that, throughout development, is selectively applied by children and adults to artifacts and biological properties. An alternative proposal ('Promiscuous Teleology') argues that teleological reasoning derives from children's knowledge of intentionality and is not restricted to any particular category of phenomena until later in development. Two studies explored the predictions of these two hypotheses regarding the scope of children's functional intuitions. Using different methods, both studies found that, unlike adults, pre-schoolers tend to attribute functions to all kinds of objects--clocks, tigers, clouds and their parts. A third study then explored this finding further by examining whether the developmental effect was due to differences in children's and adults' concept of function. It found that both children and adults predominantly view an object's function as the activity it was designed to perform. Possible explanations for the developmental differences found in the first two studies, and implications for notions of a teleological stance are discussed.