A modified method of transbronchoscopic sponge biopsy is presented a series of 212 patients is discussed. A diagnostic accuracy rate of 89 per cent was obtained in the 159 cases of proved carcinoma. False-positive and false-negative results are discussed. This technique was found to be an easy, rapid, accurate, and inexpensive method of obtaining samples for cytologic evaluation in the preoperative work-up of patients with suspected pulmonary malignancies.