Vasculitis is rare in children, and, apart from HSP and perhaps KD, most practicing pediatricians will never encounter a case. Nonetheless, progress in the diagnosis and treatment of these conditions has afforded most children with vasculitis a reasonably good prognosis. Accordingly, it is important to consider vasculitis as a potential cause of unexplained inflammation, perplexing rashes, or strange combinations of symptoms. Although evaluation and management of suspected vasculitis are difficult in the best of situations, they are impossible if the diagnosis is not considered.