This publication brings together leading emotion researchers whose work has pioneered new questions, methods, and levels of analyses for investigating development and individual differences in how infants and children attend to, categorize, understand, talk about, and regulate emotions. Topics include infant attention and processing of emotions, developmental affective psychophysiology, emotions in maltreated children, attention biases and anxiety, emotional competence and social interactions, cultural differences in emotion socialization, gender and parent-child reminiscing about emotional events, family emotion conversations and socio-cognitive development, and causal reasoning about emotions. These contributions lay a foundation for new scientific discoveries in developmental affective science, and they inform evidence-based practices and interventions aimed at promoting children's emotional wellbeing. Given the centrality of emotions to children's development, this volume provides a valuable resource for developmental researchers and clinicians, as well as for parents, educators, and policy makers.