Emotional expression is an essential component of social communication between persons of all ages. Emotions may be expressed via facial expressions, [Page 725]vocalizations, body postures, body movements, and words. Although facial expression has been the focus of most research, this is only one of many cues that people may use to discern another person’s emotion. This entry describes the historical basis for current studies of emotional expression, the emergence and development of emotional expressions in infancy and beyond, socialization influences on emotional expression, and overall age differences in emotional expressivity.