Gunilla Lindqvist argued that in playworlds teachers “step(ping) out of their ‘teacher roles’” and “dare(d) to try new attitudes and ways of acting” (1995, pp. 210-211). This paper presents cases of adult playworld participants’, ie. teachers and researchers’, ways of being in five playworlds in a variety of institutional settings in four nations: We believe that the quality of children’s experiences in these playworls depends on the quality of the experiences of the teachers, and also of the researchers participating in the projects. Teacher and researcher descriptions of their own and other participating adults’ ways of being in these playworlds was collected from completed and ongoing playworld studies, and from interviews conducted specifically for this study. Data was, thus, derived from various research projects, each at their own research sites. Different methods of analysis were used at each research site, although some forms of participatory observation, focused on the theme, narrative and process of artwork production, were common across all sites. Also allowing for the necessary coordination, while taking difference as a starting point for understanding human development, the playworlds examined in this paper were created in Sweden, Finland, Japan and the United States but were all inspired by the work of Pentti Hakkarainen; and all developed, over the past 17 years, within the International Playworld Network (IPWNW), which originated at the Laboratory of Comparative Human Cognition at the University of California, San Diego. Analysis took place using an intentionally diverse collection of theories, which reflect the diversity of perspectives that makes the IPWNW productive: Gadamer’s theories of play to describe the playworlds “playing” the teachers and researchers as play “plays” the child; Hadley’s theories of adult participation in play to understand experiences of adults playing “inside the flow” of playworlds; Miyazaki’s theory, drawing on the work of Bakhtin, of the triadic relationship between an imaginative world, children and adults; Rainio’s theorizing of dialectics of agency in adult-child interaction in playworlds; and recent developments of Participant Design Experiments.