Background: Psoriasis affects 7 million people in the United States, causing substantial cost, social stigma, and disability. Objective: The purpose of this study was to evaluate the health effects of skin disease by comparing psoriasis to other primary medical disorders using 3 different scales of health-related quality of life. Methods: A self-administered questionnaire consisting of 3 health-related quality of life measures was given sequentially to 35 eligible patients with psoriasis presenting to the Dermatology Branch of the National Cancer Institute (NCI) for an investigational therapeutic protocol. Results: All patients (100%) agreed to participate. The median Psoriasis Area and Severity Index (PASI) score was 13.0. Overall, 82.9% at least often felt the need to hide their psoriasis, and 74.3% claimed their self-confidence was at least often affected by their psoriasis. The median EQ-5D health state utility score was 13.0% less than healthy individuals (P < .001). On the SF-36, the mean general health score was 13.2% less (P = .005) and the median social functioning score 18.7% less (P = .005) than that of patients with no chronic conditions. Conclusion: Individuals with psoriasis are significantly affected in their health state utility, perception of general health, and social functioning when compared with individuals without chronic disease and those with certain primary medical conditions. (J Am Acad Dermatol 2002;47:512-8.)