In Luxembourg, like in all OECD countries, the last ten years have brought an enormous increase of non-parental care for children prior to and alongside the school. Early childhood education and care (ECEC) is not only expected to cover social needs, but to serve as an opportunity for enhanced education and learning processes. ECEC is understood as an element of a non-formal sector of education and learning for children from age 0 to 12 that is considered to be an essential stage of lifelong learning. Against this background, the proposed study investigates the care arrangements of 2 to 4-year-olds from a child-centred view and asks how these care arrangements shape the living conditions of children and thereby constitute differential childhoods in terms of the social position of children.Within this age group the boundaries between different care settings accumulate: mainly between family care and professional care, between for-profit and non-profit care, between non-familial care and preschool education. Parents make use of the range of care facilities in accordance with their living conditions and their images of ‘good childcare’. Therefore, they combine the diverse settings to complex chains of care arrangements which are embedded into their cultural and linguistic milieus. Legally constituted structures of care form only one aspect of the care system. The diversity and complexity of care arrangements reflects the user-perspective on the ECEC system. What does this mean for the children? From the vantage point of the children, this complex diversity of care arrangements forms the distinct structures of their everyday realities. These daily realities are defined by various horizontal transitions that are actively performed and shaped by the children. The project combines research on ECEC with questions of childhood sociology. The proposed study is not concerned with the effective promotion of children’s development and the effects of pedagogical programmes, but rather with the normalisation and structuration of differential childhoods. The study explores the everyday accomplishment of the Luxembourgian field of ECEC by focusing the on-going positioning of the group of the children as social actors within the field. In 12-15 case studies, the study will examine the participation of children in different kinds of individual ECEC arrangements and in various respective ECEC practices, settings and transitions. The project applies an ethnographic fieldwork approach which on the one hand is suited for gaining access to the institutional practices of education and care in day care settings. On the other hand, the ethnographic approach allows describing the constitution of the field of non-formal education by following children throughout their diverse everyday care arrangements and exploring their shifting role in the horizontal transitions between family and (different) day care settings. The project will show how the diversification of the day care sector affects the learning opportunities for children and explore both the inequality and the potentials of different care arrangements with respect to the current political ambitions in transforming day care to a special area of non-formal education.