This book integratively examines theories and models of the most essential findings of personality psychology with the aim of advancing personality knowledge. Since much empirical research is applied to very specific problems, the larger picture can get lost. Rather, this book starts from a coherent scientific theoretical framework, rather than presenting diverse theories of personality — phenomenological empirical, psychoanalytic behavioral, humanistic and cognitive perspectives — without enough critical examination. In this book, all theories, models and perspectives are reviewed and discussed within a unified theoretical framework of psychology Thus, historically and conceptually different models can be considered by scientific standards. Its insights will be highly relevant to academics, students and professional alike.