Thirty cases of Wegener's Granulomatosis are reported, 16 men and 14 women aged 49.3 +/- 14 years at the onset of their illness. The presenting symptoms were oto-rhino-laryngeal in 22 cases and pulmonary in 16 cases. Renal disease was initial in only 1 case. The complete picture comprised oto-rhino-laryngeal (29 cases), pulmonary (26 cases), renal (27 cases), articular (16 cases), muco-cutaneous (19 cases), ocular (15 cases), neurological (13 cases), and muscular (10 cases) involvement. An increased sedimentation rate, leukocytosis, anaemia and thrombocytosis were common findings. The treatment comprised steroid therapy associated with immunosuppressor drugs (28 cases) and plasma exchanges (8 cases). External radiotherapy was used in 5 patients, including 3 with bronchopulmonary lesions, but was not effective. The probability of survival after the initial symptoms was 84 p. 100 at 1 year, 69 p. 100 at 3 years and 59 p. 100 at 5 and 10 years. Eight patients died; infection and renal failure were the principal causes. Late relapse occurred in 3 patients justifying long-term follow-up and the necessity of using the term "cure" with reserve. The clinical and therapeutic aspects are described in the light of the authors' experience and a review of the literature. The concept of localised form of the disease and bordeline forms with atrophic polychondritis, periarteritis nodosa, Churg and Strauss syndrome and lymphomatous granulomatosis are also discussed.