A popular social discourse in the United States is that play is important for children's learning and that parental involvement maximizes play's learning potential. Past research has concluded that parents who hold this view of play are more likely to play with their children than those who do not. This study investigated the prevalence of this view among Euro-American and immigrant Latino parents of young children in order to illuminate the extent to which it uniquely and uniformly motivates parent-child play. Parents' models of play were assessed through interviews and naturalistic observations in a children's museum. Analysis revealed ethnic group differences in parent-child play that corresponded with parental beliefs about play. Within-group analysis, however, revealed diversity in the ways that these play behaviours and beliefs came together to comprise parents' models of play. Discussion focuses on the social nature of play, the dynamic nature of culture, and the issue of individual subject validity. Implications for the interpretation of parent--child play in early childhood settings are considered.