According to Piaget, young children have a profoundly different conception of distance than do adults. In fact, Piaget argues that young children do not have a conception of distance since they do not conceive of distance as being composed of fixed units of space. In contrast, results of a series of studies indicate that in tasks requiring distance judgments of large-scale and small-scale paths, judgments of paths with and without interposed points, and judgments of visible and unseen paths, young children's concepts and judgments of space are determined to a significant degree by a fundamentally correct conception of distance. As Piaget has argued, a conception of distance is basic for an understanding of space; such a conception occupies a fundamental position in the child's thinking and reasoning about space. In contrast to Piagetian theory, findings show that the acquisition of a concept of distance is evident quite early in development. Reproductions of 11 slides used during the presentation are appended. (RH)