This chapter considers evolutionary theories, appraisal theories, and psychological constructionist theories. It attempts to explain what roles emotion antecedents, biological givens, and integration play in each theory. Developmental theories of emotion both acknowledge that emotional development is partly preprogrammed in the organism and recognize that all aspects of emotion are responsive to the context in which the child is developing. Whereas evolutionary theories link emotions to biological adaptation in the distant past, appraisal theories link emotions to people's immediate evaluation of their circumstances. Appraisal theorists believe that very few objects or events inevitably cause the same emotion in all people. Psychological constructionists also suggest that the components of emotion are controlled by distinct neural and bodily systems that respond to particular features of the event in which an emotion was experienced. In psychological constructionist theories, the innate component of emotion is core affect. This chapter also presents an overview of the key concepts discussed in this book.