Abstract 1. 1. Suprasternal mediastinoscopy, as described in the Scandinavian literature, permits diagnostic exploration of the mediastinum, and biopsy of the paratracheal and subcervical lymph nodes, with minimal morbidity and mortality. 2. 2. Like mediastinal biopsy during standard open thoracotomy, this method is designed to supplement, not to supplant, less formidable diagnostic procedures such as scalene fat pad biopsy. 3. 3. This procedure was well tolerated by patients with impaired pulmonary function for whom standard open thoracotomy was particularly undesirable. 4. 4. Seven of 8 patients with bilateral hilar enlargement of undetermined etiology yielded mediastinal nodes that were diagnostic for sarcoidosis or tuberculosis.