We sought to examine the demographic and clinical features and psychiatric comorbidity in persons reporting compulsive computer use. Sixteen men and 5 women were recruited by advertisement and word-of-mouth. All reported excessive computer use that interfered with social or occupational functioning or caused personal distress. The subjects completed structured and semistructured assessments, including a computer version of the Diagnostic Interview Schedule (DIS), the Minnesota Impulsive Disorders Interview, the Personality Diagnostic Questionnaire-Revised (PDQ-R), and a brief version of the Medical Outcome Study Short Form-36 (SF-36). The typical subject was a 32-year-old single white man with a mean yearly income of $27,000; problem computer use began at age 29 and consumed 27 hours each week. Eleven subjects (52%) reported school or academic problems resulting from their computer use, and 12 (57%) reported that family members had confronted them about it. Thirteen subjects (62%) had tried to cut back on their computer usage. Nine subjects (43%) reported missing work or school owing to their computer use. According to DIS results, 7 subjects (33%) had a lifetime mood disorder, 8 subjects (38%) had a substance use disorder, and 4 subjects (19%) had a lifetime anxiety disorder. According to the PDQ-R results, 11 subjects (52%) met criteria for at least one personality disorder, the most frequent being the borderline, antisocial, and narcissistic types. Impulse-control disorders were also common, particularly compulsive buying. On the SF-36, subjects showed impaired mental health functioning compared with a normative sample. The results show that persons reporting compulsive computer use suffer substantial psychiatric comorbidity and show evidence of emotional distress. While the disorder appears to be increasing in prevalence, more work is needed to determine its relationship with other disorders and to determine its risk factors, family history, psychosocial complications, and natural history.