Kaposiform hemangioendothelioma is a locally aggressive, endothelial-derived spindle cell neoplasm that occurs exclusively in infants and adolescents. Lesions are characterized by rapid growth and extension, and are often associated with Kasabach-Merritt syndrome and lymphangiomatosis. Clinically nonspecific, they can appear as tender rapidly expanding red plaques, nodules, grouped papules, or telangiectasias. The histology is distinctive, however, as it combines features of tufted angioma, progressive lymphangioma, and Kaposi's sarcoma in a characteristic pattern. We describe a patient with kaposiform hemangioendothelioma currently controlled with systemic prednisone. (J Am Acad Dermatol 1998;38:799-802.)