A patient with silicosis and progressive dyspnea on exertion is described in whom open lung biopsy revealed active chronic inflammation with many macrophages filling alveolar spaces. Because of the extensive involvement by the disease of small air spaces, bilateral whole lung lavage was performed. The lung lavage effluent was striking in its blackish brown color. It was composed predominantly of macrophages containing silica, silicates, and graphite. Particles in the tissue and lavage were analyzed using scanning electron microscopy and energy dispersive X-ray analysis. The dry weight of the material removed was approximately 25 g, of which an estimated 135 mg was silica. The procedure resulted in immediate symptomatic improvement in the patient. Although his pulmonary function did not change significantly, it is hoped that removal of this material will improve his long-term prognosis.