This study examined the influence of motor enactment on the formation of mental images. Following a procedure originally used by Piaget and Inhelder in 1971, 5-yr.-old children were assigned to one of four treatments. They visually examined block configurations, imagined the construction of the configurations, imagined enacting the construction, or carried out the actual construction. When the original configurations were removed, the children were asked to reconstruct them from memory. Analysis showed that the children in the imaginary enactment and actual construction conditions were more accurate than those in the other conditions. The findings are discussed as supporting an action-based understanding of imagination.