The systemic vasculitides are a wide-ranging group of diseases that are characterized by the presence of blood vessel inflammation. Despite this common feature, each type of vasculitis has a unique variety of clinical manifestations that influences its degree of disease severity and ultimately its management. Immunosuppressive therapy forms the foundation of treatment for almost all forms of systemic vasculitis. Because of this, treatment can be associated with its own risk of morbidity, or even mortality, related to specific medication side-effects or infections which occur as a result of impaired host defences. This chapter seeks to review the approach to management in selected forms of systemic vasculitis. Questions examined include the following. When should one treat systemic vasculitis? How does the nature of the disease and its severity affect treatment decisions? What are the data regarding the effectiveness of individual therapeutic regimens?