Vitiligo is an acquired depigmentary disorder of the skin that results from the selective destruction of melanocytes. The etiology of vitiligo is poorly understood. There appears to be a genetic predisposition, but additional factors are probably involved. The purpose of this article is to outline the factors that might play a role in the development of vitiligo. These include trauma such as vaccination, radiotherapy, and sun exposure, malignancies and treatment of malignancies like lymphoma or melanoma, bone marrow transplantation, interferon, interleukin, and other drugs, psychological factors, endocrine disease and cytotoxic compounds that cause contact vitiligo. We hope future research will shed more light on the subject and identify the precipitating factors, since in the majority of vitiligo cases the contributing factors are as yet unidentified.