NORC at the University of Chicago designed and implemented an impact evaluation of the SEEDS of Learning (SEEDS) professional development (PD) program on behalf of the Kenneth Rainin Foundation, in collaboration with Kidango. SEEDS of Learning is an evidence-based PD program that prepares early childhood educators to help children develop the social-emotional, language, and emergent literacy skills they need to be kindergarten-ready. The purpose of the study was to evaluate the impact of the SEEDS PD program on students' oral language, literacy, and social-emotional outcomes. Using a clustered randomized controlled trial design, the study found positive impacts on early literacy skills, with the largest impacts in Year 2 of implementation, after the program experienced learning over time to better implement the SEEDS program. [This study was conducted with support from the Kenneth Rainin Foundation and in collaboration with Kidango.]