The emotional competencies of each period of childhood are situated within social relationships and cultures. This chapter describes contributions of emotional competence to social competence within differing relationships. Emotional competence is the ability to fully experience and express a variety of emotions, regulate emotional expressiveness and experience when necessary, and understand the emotions of self and others. Culture-specific socialization goals are related to the development of children's emotion regulation. Emotion knowledge conveys crucial interpersonal information, guiding interaction. The asymmetrical nature of the parent–child relationship facilitates socioemotional development in several ways. Parents are children's primary attachment figures who assist with co-regulation of emotion. A mixture of perspectives and methods – self- and third-party assessment, using both ratings and observations, should be most useful in obtaining a comprehensive picture of children's emotional competence. Children with higher emotional competence tend to have more friends or make more friends over time.