Narcissistic personality disorder is a mental disorder in which people have an inflated sense of their own importance, a deep need for admiration and a lack of empathy for others. According to the Mayo Clinic this overwhelming confidence is just a mask that cover a very fragile sense of self-esteem that is vulnerable to the slightest criticism. People with narcissistic personality disorder often have problems functioning in a job or at school, in a relationship, or with personal finances. They tend to become unhappy or disappointed when they do not receive the special favors or admiration that they feel they deserve. Treatment usually consists of psychotherapy. To read this article in its entirety, click here.