Personality disorders are a group of psychiatric conditions in which chronic behavior patterns cause serious problems with relationships and work.
The exact cause of personality disorders is unknown. However, many genetic and environmental factors are thought to play a role.
Mental health professionals categorize these disorders into the following types:
Moore DP, Jefferson JW, eds. Handbook of Medical Psychiatry. 2nd ed. Philadelphia, Pa: Mosby Elsevier; 2004: chaps 134-143.