ABSTRACT: The disease pathway of the skin pigmentary disorder vitiligo involves hereditary factors, disease onset after overproduction of reactive oxygen species, and disease expansion through an adaptive, antigen-specific immune response to melanocytes. The current study was performed to obtain further knowledge of the disease process through patient questionnaires. Fifteen questions describing the condition of vitiligo were posted on the National Vitiligo Foundation and Vitiligo Support International Web sites and distributed by participating dermatologists to patients visiting their clinics. A total of 400 responses to the survey were collected and subjected to statistical analysis. The data support an overall increase in affected skin averaging 1% per year, with 50% of patients displaying a Koebner phenomenon, where new skin lesions appear at sites of trauma. Approximately 25% more women than men develop the disease. Patients recognize the importance of hereditary factors and the involvement of stress in precipitating the disease, yet only few note the contribution of an autoimmune response. Patients with relatives affected by vitiligo demonstrated an earlier age of onset. Autoimmune diseases found to be at least 25-fold more prevalent among respondents include Addison's disease, sarcoidosis, diabetes, and alopecia areata. Among a third of patients currently undergoing treatment, half note satisfactory efficacy, in particular for depigmentation treatment or topical immune modulation. The study has provided new insight into vitiligo disease parameters.