This volume focuses on social and emotional learning (SEL) from a variety of perspectives. The goal of the volume is to offer a clear framing of SEL in relation to other related out—of—school time concepts and initiatives. SEL has gained popularity as a concept in recent years and there remains confusion as well as great interest in the meaning and implementation of SEL in OST. Policymakers, researchers, and practitioners are pursuing work related to SEL in OST and this volume offers an opportunity to share that work by: • Defining and explaining SEL in a variety of out of school contexts and highlighting opportunities for integration and alignment with other fields (e.g., formal education) • Clarifying the language and framework confusion and honoring the field’s foundation in thinking about social and emotional development through high quality youth development practice • Sharing information about current trends and new developments and how that work is shaping the field across the developmental continuum • Making the research to practice connection by including in each chapter foundational research on the topic, evidence of effective efforts, and practical implications • Offering recommendations for researchers, practitioners, and policymakers related to SEL in OST settings