Socialization with peers is one of the main goals of early childhood education and care outside of the family but the processes of young children's sociality in ECEC centres are still to be fully understood. This chapter presents an analysis of toddler's sociality with peers during their everyday life in an ECEC centre, based on ethnographic data (videos and written notes) collected during a whole morning within the toddler program of a municipal nido in Italy. It highlights that in a group situation children's attention is aroused by a multiplicity of social stimuli and that they often participate in joint activities with peers. The analysis of toddlers' participation shows that both social and cognitive processes converge in children's sociality with peers and contribute to make the ECEC experience an important step in the course of their life. Implications for educational practices in ECEC centres are also discussed.
