An ideal text for advanced students and a timely reference for researchers and clinicians, this influential work examines how enduring dispositions or traits affect the process of aging and shape each individual's life course. In the process, it offers a comprehensive and accessible introduction to the Five-Factor Model of personality. From two well-known authorities in the field, the volume is grounded in a growing body of empirical evidence. Special attention is given to how research on the Five-Factor Model can contribute to the development of a comprehensive theory of personality.