The self has emerged as a central construct in many domains of behavioral and social science. This state-of-the-science volume brings together an array of leading authorities to comprehensively review theory and research in this burgeoning area. Coverage includes the content, structure, and organization of the self; processes related to agency, regulation, and self-control; self-evaluation and self-related motivation and emotion; interpersonal and cultural issues; and self-development across evolutionary time and the lifespan. Also examined are ways that the development of the self can go awry, resulting in emotional and behavioral problems.