Experience of fluoroscopically controlled transbronchial biopsy using the fibreoptic bronchoscope in 30 patients with solitary lesions in the peripheral lung fields beyond bronchoscopic vision is described. At the time of submitting this paper for publication (30 January 1978) no account of the technique has been reported in the British literature. In 21 patients with a final diagnosis of bronchial carcinoma a positive biopsy diagnosis was obtained in 14 (67%). Five of seven patients (71%) with a final diagnosis of an inflammatory condition showed evidence of acute or chronic inflammation on biopsy. There were no complications. The procedure is indicated when a definitive diagnosis is required for management planning in clinically inoperable patients, or when a tissue diagnosis is particularly desired in an attempt to obviate the need for thoracotomy. The relative safety makes this the biopsy technique of choice for the evaluation of isolated peripheral pulmonary opacities.