Eighty-two patients with superior vena-caval obstruction (SVCO) were studied retrospectively. Carcinoma of the bronchus was responsible for the syndrome in 60 patients; of the remaining 22 patients, 7 had mediastinal lymphomas, 5 retrosternal goitres, 4 oesophageal cancer, 3 vascular aneurysms, 2 thymic tumours, and 1 granulomatous mediastinitis. Rigid bronchoscopy, scalene node biopsy or aspiration, cervical mediastinoscopy, anterior mediastinotomy, transthoracic needle biopsy and median sternotomy were the procedures used to make a definitive diagnosis. It is noteworthy that in 9 of the 82 patients malignant disease was not the cause of the SVCO. Seven of the remaining 73 patients had lymphoma causing compression of the superior vena cava. A significant proportion (19.5%) of urban Blacks with SVCO had causes other than hopeless bronchogenic carcinoma as the basis for their condition.