As the average age of the population rises, mental health professionals have become increasingly aware of the critical importance of personality in mediating successful adaptation in later life. Personality disorders were once thought to age out, and accordingly to have an inconsequential impact on the lives of the elderly. But recent clinical experience and studies underscore not only the prevalence of personality disorders in older people, but the pivotal roles they play in the onset, course, and treatment outcomes of other emotional and cognitive problems and physical problems as well....