Piaget's early contribution to theorizing about play is discussed critically with reference to three major interrelated problems. These are: (1) that despite their equipotentiality in Piaget's theory of intelligence, imitation and play are not conceptualized as making an equal contribution to cognition, play taking a subordinate role; (2) that this inequality was brought about by Piaget's focus on directed or rational or convergent, rather than undirected or imaginative or divergent, cognitive operations; and (3) that it was also a result of presupposing play to be a predominantly infantile state of development, a not uncommon assumption in the work ethic ideology of Western culture. A review of three kinds of research--therapeutic, animal and child experimental--indicates support for Piaget's notion that play does not contribute as importantly to cognition as do imitation and exploration. It is argued, however, that Piaget has paid attention only to lower level and more content influenced categories of play. Borrowing from communication and cultural theories of play, a hierarchy of structural categories is proposed which suggests deeper levels of operations in play. These categories are reframing, reversal, abstraction of prototypes, theme and variation, boundaried space-time, and modulation of excitement. It is also argued that Piaget tended to study the infant in a solitary situation and to assume that his own presence had minimal influence on the infant's behavior, and that this predisposed him towards a view of play as reverie. It is proposed that a more comprehensive view of play should take into account adult and social-cultural forms of play. (Author/SS)