In 1908, the Nobel Prize in Physiology and Medicine was shared by Elie Metchnikoff and Paul Ehrlich. Their joint commendation acknowledged the vigorous debate which then existed and, in a sense, paved the way for our modern recognition that both cellular and humoral mechanisms might participate in immunity. Of Ehrlich's and Metchnikoff's many accomplishments, those concerning the basic nature of the inflammatory reaction suggested a clinical potential that has been realized only in the last decade. Central to their theories was the implication that normal inflammatory processes were of benefit to the host and that disordered inflammation was likely to lead to disease. Over the past decade or so, we have recognized an extensive set of diseases associated with primary or acquired deficiencies of inflammation, thus beginning to catch up to the genius of Ehrlich and Metchnikoff. Most, if not all, of these disorders demonstrate major cutaneous involvement in their clinical and biologic presentations. It is thus of essential importance that the dermatologist be familiar with this fascinating spectrum of disease, and it is to this end that this review is directed.