Personality disorders have in common unhealthy, rigid thinking patterns, maladjusted behavior and disturbed functioning. Personality disorders cause trouble in relating to people and situations because of distortions in perception. People with personality disorders likely have difficulty and limitations socially, educationally and occupationally. You may not realize that you have a personality disorder, because the ways you think and behave feel natural to you. You may feel that others are responsible for your difficulties. There are three clusters of personality disorders: odd or eccentric disorders; dramatic, emotional or erratic disorders; and anxious or fearful disorders. The onset of these disorders usually begins in adolescence or early adulthood and may become less evident during middle age. Treatment of personality disorders includes helping you to become more aware of your thinking and behavior, which empowers you to self-regulate more effectively.