The fifth edition of this text is a theory-by-theory approach to help students develop the skills they need to critically evaluate theories. In the beginning of the book, the author defines personality, provides basic information concerning the scientific process and the interrelatedness of theory and research, and offers the criteria scientists use in judging a theory. Then, chapter by chapter, the book introduces each major theoretical position with an objective overview of the theorists' basic concepts and principles. A rewritten final chapter reviews the current status of the theories and their contributions to understanding of the nature of human personality. It also highlights the heuristic value of the theories, noting the many ways in which they act as stimulants to the thinking and research efforts of personality psychologists. Ryckman finishes by presenting information about the discipline's prospects for the future.