The purpose of this systematic review and meta-analysis was to evaluate the associations between educator early childhood specialization and children’s cognitive, academic, physical, social, emotional, and behavioral outcomes. We focused on preschool aged children. Searches of PsycINFO, ERIC, and Medline, websites of large databases, and reference sections of all included studies were conducted up to February 5, 2018. Title, abstract, and paper reviews were conducted by two independent raters to include studies that provided a statistical link between educator early childhood specialization and child outcomes. Sixteen eligible studies (21 samples, n = 15,157 children) were included in the systematic review. Heterogeneity between studies was identified in terms of how educator early childhood specialization was operationalized, conceptualized, and measured. (author abstract)