From a child-centered perspective, this article explores the practices of children's self-organized play-communities in institutional everyday life in Danish early childhood education and care (ECEC) settings, based on a phenomenological non-participant-observational study with a duration of 16 months involving two kindergartens (Bernstorff, 2021). Drawing on Bourdieu's reflexive sociology and praxeology, children's self-organized play-communities are analyzed as a social space, being a field for relations, fights, negotiations with specific admission requirements emerging as accepted values shared by the specific field. The analysis demonstrates that self-organized play-communities are a social space with its own practices of "being together" expressed through "the social language in play" linked to and guided by an "institutional choreography." Besides, the analysis demonstrates three kinds of different communities of children in self-organized play, viz. the categories: "Relational play-communities," "Community-oriented play-communities," and "Conflictual play-communities," which categories may, however, also overlap into blended categories. The article argues that children's self-organized play-communities risk being under pressure in the institutional choreography, which in turn affects children's opportunities for having uninterrupted periods of time and space to self-organized play in their institutional everyday life.