In the past, researchers have treated the development of the emotions and the task of emotional regulation as two separate topics, the former emphasizing 'normative' questions and the latter emphasizing 'individual' differences. Until now, understanding the first topic has never been seen as relevant for the second. This is the area pioneered by Emotional Development. This book presents the early phases of emotional life from a developmental perspective. It argues that emotional generation hinges on the developing ability to express arousal or 'tension' in accordance with one's context. It reveals the common core processes underlying the emergence of specific emotions and the capacity for emotional regulation. It explains the timing of emotional emergence, why emotions function as they do, and also explores individual styles of emotional regulation. Close ties between emotional development, cognitive, social and CNS development are discussed, too.