How does teacher–child interaction quality in early child care and education settings influence the development of social-emotional skills in children at around two to three years of age? We measured the quality of interactions on the side of the child care teachers (N = 9, CLASS Toddler) and assessed self-regulatory skills through an individual assessment (i.e. working memory by the “Hidden Toys Task”, selective attention with the NEPSY, inhibitory control by using the “Toy Wrap Task”), testing children between 22 and 45 months old (M = 33 months, SD = 6 months; N = 64; 44% girls) who attended a child care center. Additionally, children’s social and self-regulatory skills were assessed by their teachers by using the MASCS and CBRS rating scales. We found evidence that for even children this young, the quality of interactions in child care settings is positively related to working memory, and less disruptive behavior. Conversely, we found no evidence that interaction quality influenced other aspects of social-emotional development, such as selective attention, inhibitory control, self-regulatory skills, prosocial behavior and impulsiveness. Results emphasize the importance of positive interaction in child care settings for children at about the age of three. Possible reasons for null findings are discussed.