Early care and education (ECE) professionals' social and emotional well-being has emerged as an area of focus for improving program quality. ECE professionals are experiencing increasing levels of stress and burnout, which is threatening the quality of early childhood education and care. This article introduces the special issue devoted to understanding early childhood professionals' social and emotional competence and well-being and their relationship to program quality and child outcomes. The purposes of this special issue are to (a) describe the nature of ECE professionals' social and emotional competence and well-being, (b) understand the factors that contribute to ECE professionals' social and emotional competence and well-being, (c) understand to what extent and how ECE professionals' social and emotional competence and well-being impacts classroom quality as well as children's developmental outcomes, and (d) present evidence-based approaches that support ECE professionals' social and emotional competence and well-being. For the purposes of this issue, ECE professionals include early childhood educators (e.g., teachers or home-based child care providers), practitioners (e.g., home visitors, mental health consultants, specialists, etc.) and early childhood leaders (e.g., directors, principals, or administrators) who serve children from birth to third grade. In this introductory article we conclude with a discussion of implications of this research for future research, policy, and practice. Early care and education (ECE) professionals' social and emotional well-being has recently emerged as an area of focus for improving program quality. ECE professionals are experiencing increasing levels of stress and burnout which is threatening the quality of early childhood education and care. Furthermore, since the advent of the COVID-19 pandemic, educator well-being is now even more salient, as schools, childcare centers, and other providers try to figure out how to safely provide muchneed care for working families while protecting their workforce from the novel coronavirus. Indeed, we are on the verge of a childcare crisis. Providers, already operating with inadequate resources and with no financial cushion, cannot survive long closures, leaving educators without jobs, and parents without childcare (National Association for the Education of Young Children, 2020). Now, more than ever, early care and education professionals' well-being is paramount. Jennings and Greenberg (2009) prosocial classroom model highlights the importance of teachers' social and emotional competence and well-being in promoting healthy teacher-student relationships, effective classroom management, and effective social and emotional learning programs. ECE professionals' psychological well-being, such as depression, stress, burnout, and emotional competence (e.g., mindfulness, emotion regulation, coping, etc.) have been shown to relate to their practices and responsiveness in the ECE setting (