We used a multiple-probe single-case research design to examine the effect of a professional development package that included real-time, technology-enhanced, and performance-based feedback and video analysis on three preschool teachers’ use of naturalistic instruction targeting children’s communication and child responses. We also measured the quality of the teachers’ naturalistic instruction targeting children’s communication. The professional development package was effective in enhancing teachers’ use of naturalistic instruction targeting children’s communication. In addition, children responded and teachers enhanced the quality of naturalistic instruction targeting children’s communication. Teachers maintained their use of naturalistic instruction targeting children’s communication upon removal of the intervention condition. (author abstract)