The evidence base for treatment of systemic vasculitis is reviewed in this article. Accurate diagnosis and evaluation of disease status is crucial to the appropriate management of these cases and disease status should be employed as a means of staging so that appropriate therapy can be offered tailored to the individual requirements of each case. Large vessel vasculitides are almost exclusively managed with corticosteroids. Small vessel vasculitis with internal organ involvement usually requires more aggressive immuno-suppression; by contrast, small vessel vasculitis without internal organ involvement rarely requires intervention. Despite our current efforts, the long-term morbidity of patients with systemic vasculitis remains high. We need better therapeutic strategies in order to limit or control disease rapidly and thereby prevent the accumulation of subsequent damage. Large-scale randomised trials comparing different therapeutic strategies offer the only hope of establishing a firmer evidence base for the optimal management of these diseases.