Vasculitis is usually a multisystem disorder that presents in a myriad of ways. Diagnosis is based on a detailed history and careful examination. Patients may present to different specialties and their care should be led by a multidisciplinary team involving physicians with a specialist interest in vasculitis. Vasculitis can be classified by aetiology or by calibre of the vessel involved. The accepted nomenclature was defined by an international consensus meeting held in 2012; cutaneous vasculitides are considered under the umbrella of ‘single organ vasculitis’, although the classification has been expanded in this chapter. Ill‐defined entities that do not have an identified pathological basis have not been included. It should be recognized that names and classifications will change in the future with greater understanding of the underlying mechanisms of disease. The treatment of primary vasculitis involves immunosuppression. The balance between disease severity and adverse effects of treatment requires expertise and experience in management of these rare conditions. Secondary vasculitis may be due to infection, drugs, malignancy or inflammatory disease. Treating the underlying condition may resolve the vasculitis.

Keywords vasculitis, immunosuppression, corticosteroids, antineutrophil cytoplasmic antibody, ANCA, single‐organ vasculitis, cutaneous arteritis, disease severity