Personality disorders are conditions in which a person has a lasting pattern of inner experience and behavior that is significantly different from the expectations of the individual’s culture. In addition, the disorder is pervasive and inflexible, begins in adolescence or early adulthood and remains stable over time, leading to some form of distress or impairment.

A person’s personality is made up of lasting patterns of perceiving, relating to and thinking about oneself and the surrounding environment. It is formed by a combination of heredity and early life experiences and involves distinctive traits, behavior styles, attitudes, thoughts and feelings. 

A person with a healthy personality is able to form relationships with family, friends and co-workers and to cope with everyday stresses that arise. However, those with personality disorders have traits that cause them to think and behave in ways that are socially distressing. They struggle to get along with other people and to have successful careers, tend to be inflexible, and are unable to respond to life’s changes and demands. Despite these difficulties, people with personality disorders usually believe their thoughts and behaviors are correct and are unable to recognize the mental health disorder.

A person’s ethnic, cultural and social backgrounds also play a role in determining whether a personality disorder exists. For example, the habits, customs, religious and political values that appear inappropriate in one culture may be entirely appropriate in another.

The onset of personality disorders usually takes place no later than early adulthood. However, in many cases the disorder is not diagnosed until years later. In addition, personality disorders are rarely diagnosed in childhood and adolescence, because symptoms that appear similar to those of a personality disorder are frequently examples of temporary conditions that pass when the child enters adulthood.