To facilitate the clinical understanding of Wegener's granulomatosis, the morphological changes involved are discussed. Such changes may be found in the entire respiratory tract or may be limited to either the upper or the lower respiratory tract with varying severity. When confronted with the nasopharyngeal course of the disease, the ENT specialist should realize that nasal and pulmonary variants can coexist. Classifications such as Granuloma gangraenescens, lethal midline granuloma or midline granuloma stress localized processes and fail to associate possible pulmonary involvement or manifestation in other organs. Such descriptions are therefore unsuitable for an understanding of the disease.