The systemic vasculitides are an uncommon group of autoimmune diseases capable of causing multi organ failure and death. Current immunosuppressive strategies have substantially improved the outcome, but the natural history of treated disease is unstable, typically characterised by frequent relapses, drug toxicity and an increasing burden of damage. Early diagnosis, accurate staging and regular evaluation of disease status are important in the management of the vasculitides. Clinical evaluation tools have been developed and provide a comprehensive assessment of patients. Serological markers, especially anti-neutrophil cytoplasm antibody (ANCA), pathology and imaging investigations are a useful addition, but are more valuable in diagnosis rather than monitoring of disease activity. Advances in magnetic resonance imaging in large vessel vasculitis have improved our ability to characterise disease and may lead to earlier diagnosis and better control in future. Development of new biomarkers is required in vasculitis, and this is likely to advance our understanding as well as the management of these complex conditions.