Section 1: Borderline personality disorder is a serious mental illness marked by unstable moods, behavior, and relationships. Because some people with severe borderline personality disorder have brief psychotic episodes, experts originally thought of this illness as atypical, or borderline, versions of other mental disorders. While mental health experts now generally agree that the name "borderline personality disorder" is misleading, a more accurate term does not exist yet. The symptoms of borderline disorder were first described in the medical literature over 3000 years ago. The disorder has gained increasing visibility over the past three decades. The full spectrum of symptoms of borderline disorder typically first appears in the teenage years and early twenties. Although some children with significant behavioral disturbances may develop readily diagnosable borderline disorder as they get older, it is very difficult to make the diagnosis in children. It is estimated that more than 14 million American adults, distributed equally between men and women, have borderline personality disorder. It is more common than schizophrenia or bipolar disorder: an estimated 11% of outpatients, 20% of psychiatric inpatients and 6% of primary care visits meet the criteria for the disorder. Obtaining an accurate diagnosis can be difficult. As ,ost patients with bipolar disorder go years before receiving an appropriate diagnosis and starting mood stabilizers[1] As with all personality disorders, the person must be at least 18 years old before they can be diagnosed with it. Borderline personality disorders is typically diagnosed by a trained mental health professional, such as a psychologist or psychiatrist. Family physicians and general practitioners are generally not trained or well-equipped to make this type of psychological diagnosis. Researchers today don’t know what causes