Research Findings: This study investigated relations among preschool teachers' (n = 75) sense of community, classroom language and literacy instructional quality, and children's (n = 398) gains in vocabulary and print concept knowledge during an academic year. Hierarchical linear modeling (HLM) results indicated that teachers' language and literacy instructional quality significantly predicted children's gains in print concept knowledge. Also, HLM results revealed significant interactions among teachers' sense of community, language and literacy instructional quality, and vocabulary and print concept knowledge gains. Higher levels of teachers' sense of community were associated with greater gains in children's vocabulary and print concept knowledge when children were in classrooms with higher quality language and literacy instruction. Practice or Policy: Findings underscore the importance of evaluating both language and literacy instructional quality and teachers' sense of community when considering high-quality preschool education. (Contains 5 tables and 3 figures.)