From 1968 to 1987, mediastinoscopy was performed on 2021 consecutive patients. The procedure was carried out in 35.7 per cent on patients with a pulmonary infiltrate and in 28.8 per cent with bronchogenic carcinoma. Mediastinoscopy was positive in 54 per cent of the cases. The total number of complications was 2.3 per cent (47/2021). There were four cases with major haemorrhage, three tracheal ruptures and three wound infections. Recurrent nerve paralysis was verified in three patients and pericardial rupture in two patients. The total of major complications was 0.5 per cent (10/2021). There was no deaths in this series. In the authors' opinion, mediastinoscopy can be regarded as an effective and safe procedure in the hands of an experienced surgeon.