Play is defined as a state of experience in which the actor's ability to act matches the requirements for action in his environment. It differs from anxiety, in which the requirements outnumber the ability, and from boredom, in which the requirements are too few for the ability level of the actor. Games are reviewed with illustrations from a cross-cultural context of traditional and modern societies. It is suggested that games of skill, strategy, and chance all share structural characteristics that allow the player to limit his experiences so as to maximize the play experience as defined. Further theoretical implications are drawn from the model in terms of the relationship of individuals and the social system.