Kawasaki disease is an acute febrile, systemic vasculitic syndrome of an unknown etiology that primarily occurs in children younger than five years of age. The principal presentations of Kawasaki disease include fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develops in 15% to 25% of untreated children with the disease, which may later lead to myocardial infarction, sudden death, or ischemic heart disease. Treatment with intravenous gamma globulin (IVIG) is effective, but the mode of action is still unclear. The development of a diagnostic test, a more specific therapy, and ultimately the prevention of this potentially fatal illness in children are all dependent upon the continued advances in determining the etiopathogenesis of this fascinating disorder.