Wegener granulomatosis (WG) is a necrotizing, granulomatous vasculitis that has a clinical predilection to involve the upper airways, lungs, and kidneys.1Although the first case was reported by Klinger in 1931, Friedrich Wegener in 1936 characterized the unique clinical and pathological features of this disease that subsequently came to bear his name. Vascular inflammation and occlusion leading to tissue ischemia is a hallmark of WG. Although strong evidence indicates that such blood vessel damage is immunologically mediated, the mechanisms that initiate this process are still largely unknown.2To date, there has been no clearly established association with genetic factors, specific infectious agents, or environmental irritants, although speculation has remained that these may play a role in triggering the onset of disease. Until the introduction of therapy with cyclophosphamide (CYC) and glucocorticoids, WG was uniformly fatal. Although drug toxicity and disease relapse remain of concern with this regimen, it has provided us with a successful means of treatment and the opportunity to better understand this disease through long-term patient follow-up.