Diagnosis of anti-neutrophil cytoplasmic antibodies(ANCA)-associated vasculitis is usually not difficult in patient with systemic disease, including lung and kidneys involvement, and laboratory signs of inflammation. The presence of ANCA and the results of histological investigation confirm diagnosis of ANCAassociated vasculitis. Cyclophosphamide/azathioprine in combination with high dose steroids are used to induce and maintain remission of systemic vasculitis. The clinical trials also showed efficacy of rituximab that induces depletion of B-cells. Our understanding and management of ANCA-associated vasculitis improved significantly over the last decades but there is still a lot of debate over its classification, diagnostic criteria, assessment of activity and optimum treatment. Diagnosis of anti-neutrophil cytoplasmic antibodies (ANCA) -associated vasculitis is usually not difficult in patient with systemic disease, including lung and kidneys involvement, and laboratory signs of inflammation. The presence of ANCA and the results of histological investigation confirm diagnosis of ANCAassociated vasculitis . The clinical trials also showed efficacy of rituximab that induces depletion of B-cells. Our understanding and management of ANCA-associated vasculitis improved significantly over the last decades but there is still a lot of debate over its classification, diagnostic criteria, assessment of activity and optimum treatment.