Over the past decade, behavioral scientists have uncovered a surprising set of social-cognitive abilities in the otherwise humble domestic dog. These abilities are not possessed by dogs' closest canine relatives, wolves, nor by other highly intelligent mammals such as great apes. Rather, these skills parallel some of the social-cognitive skills of human children. On page 1269 of this issue, Topál et al. extend our understanding of these specialized abilities, showing that in some situations, they may lead man's best friend, just as they do young children, into curious errors.