This dissertation research applies an ecological perspective to classroom-based emotion socialization to examine how relational features of educational environments outside the home are related to children’s social-emotional development. It will be a three-paper dissertation comprising one theoretical and two empirical papers. This research is motivated by the following objectives: (1) to explore a conceptual model elucidating the relational processes underlying emotion-related socialization in the classroom, with a particular focus on how these processes differ from current models for parent socialization; (2) to test this model by investigating associations between various socialization processes within the preschool setting, as well as their relation to children’s social emotional skill development; and (3) to examine the degree to which early educational contexts can be grouped according to particular profiles of socialization and determine whether socialization profiles are differentially related to children’s social-emotional development. To address these objectives, this study uses data from the Early Learning Study at Harvard collected in 2018-19 and the Head Start CARES study collected in 2009. (author abstract)