Hansen's disease is a chronic granulomatous disease of infectious origin. It has a worldwide distribution and a variety of clinical manifestations often involving the skin, nasal mucosa, and peripheral nerves. Lepromatous leprosy characterizes the condition of a large group of patients with little or no resistence to the infection. Several forms of lepromatous leprosy are recognized, including macular, nodular, and diffuse. Lucio's phenomenon is a rare but distinctive skin eruption seen in patients with diffuse lepromatous leprosy. The diffuse lesions of Lucio's phenomenon have a predilection for the extremities, can include nodules, and heal with atrophic stellate scars; histologically, a necrotizing vasculitis accompanied by a nonspecific inflammatory reaction may be seen. We describe two patients with Lucio's phenomenon who presented with nontender, painless, skin lesions with nodules in part perceptible only by palpation. Both patients were treated with multidrug therapy, and immunosuppressive doses of steroids as the suggested optimal treatment for this reactional state. However, Lucio's phenomenon is frequently fatal as a result of bacterial infection or sepsis, and both patients reported here died. We call attention to this particular and unusual skin manifestation of lepromatous leprosy, which can mimic rheumatic disease and other causes of vasculitis. This is especially likely to be unrecognized in nonendemic countries but cases will occasionally be seen in this age of extensive international travel.