48 Korean- and 48 Anglo-American children were observed in their preschool settings to examine the role of culture in organizing children's activities and in shaping their pretend play behavior. Observers recorded the presence or absence of preselected social behaviors and levels of play complexity. Parents completed a questionnaire about play in the home, teachers rated children's social competence, and children were given the PPVT-R and a socio-metric interview. Korean parents completed an acculturation questionnaire. The findings revealed cultural differences in children's social interaction, play complexity, adult-child interaction and play in the home and in the preschool, adult beliefs about play, scores on the PPVT-R, and children's social functioning with peers. The results suggest that children's social interaction and pretend play behavior are influenced by culture-specific socialization practices that serve adaptive functions.