To assess the contribution of flexible fiberoptic bronchoscopy to the evaluation of suspected cases of pulmonary tuberculosis, the records of 41 patients with pulmonary tuberculosis proved by culture who underwent bronchoscopy were reviewed. Three or more expectorated sputum specimens were obtained before bronchoscopy in 37 patients and failed to reveal stainable mycobacteria; no sputum could be obtained from 4 patients. Bronchoscopy specimens revealed stainable mycobacteria in 14 of 41 patients. Cultures of bronchoscopy specimens from 39 of 41 patients were positive for Mycobacterium tuberculosis and provided the exclusive culture-positive specimen in 19 of 41 patients. Pathologic examination of lung biopsy specimens revealed granulomas in 8 of 29 patients and coexisting bronchogenic carcinoma in 4 patients. The appearance of the bronchial mucosa was varied and diagnostically nonspecific. There were no significant complications of bronchoscopy. Flexible fiberoptic bronchoscopy is useful in the evaluation of suspected cases of pulmonary tuberculosis in patients with negative smears. Bronchoscopy frequently provides positive smears and cultures for M. tuberculosis when pre-bronchoscopy sputum examination fails and is useful in diagnosing coexisting bronchogenic carcinoma.