An 11-year-old white boy had Wegener's granulomatosis, a rare condition in the pediatric age group. The clinical course, pathological findings, and mode of treatment are outlined. The disease is in remission on a regimen of cyclophosphamide therapy as judged by both clinical and pathological criteria. This syndrome with protein manifestations should be considered in children with symptoms of repeated upper respiratory tract infections along with pulmonary and renal involvement. Early renal biopsy helps to establish the diagnosis of generalized involvement and to guide the course of treatment. Follow-up renal biopsies may serve as an indication for the continuation of treatment. Cytotoxic agents, especially cyclophosphamide, dramatically alter the course of the disease.