The vasculitides are a heterogeneous group of disorders that cause blood vessel inflammation and necrosis. Vasculitis may represent a primary disease process or a secondary manifestation of an underlying systemic condition. Neurologic symptoms and signs are common in most of the vasculitic syndromes and may be the presenting (or only) manifestation of the disease. Careful consideration of appropriate clinical, laboratory, radiologic, and histologic data will usually suggest the correct diagnosis. A systematic diagnostic and therapeutic approach is crucial in these patients, as immunosuppressive therapy is effective in many of these disorders.