In psychology, ajustment disorder (AD) is a classification of mental disorder that is a psychological response from an identifiable stressor or group of stressors that causes significant emotional or behavioral symptoms that does not meet criteria for more specific disorders. The condition is different from anxiety disorder which lacks the presence of a stressor, or post-traumatic stress disorder and acute stress disorder which usually are associated with a more intense stressor. There are nine different types of adjustment disorder listed in the DSM-III-R. In DSM-IV, adjustment disorder was reduced to six types, classified by their clinical features. Adjustment Disorders may also be acute or chronic, depending on whether it lasts more or less than six months. Diagnosis of adjustment disorder is quite common; there have been reports of it being a common and serious condition among adolescents and it has estimated incidences of 5-21% in psychiatric consultation services for adults. In clinical samples of adults, women are given the diagnosis twice as often as men.