Pleuro-pulmonary manifestations are frequent in systemic lupus erythematosus (SLE), being found in 40 to 70% of patients with this disease. However, these manifestations can be attributed to SLE only when other pathologies, and notably infections, have been excluded. The truly SLE-related pleuro-pulmonary manifestations can be divided into five types: pleurisy, interstitial pneumonia, lupus pneumonia and two new entities: diffuse pulmonary haemorrhage and pulmonary arterial hypertension. The most frequent manifestation, pleurisy, only requires symptomatic treatment combined with non-steroidal anti-inflammatory agents. Corticosteroids are seldom necessary, but they must be used in lupus pneumonia or in diffuse interstitial pneumonia, owing to the severity and potentially poor prognosis of these two manifestations. Pulmonary haemorrhage is a serious and probably underestimated manifestation; it is diagnosed by bronchoalveolar lavage which also enables other causes, in particular infections, to be excluded. As soon as the aetiological diagnosis is made, high-dose corticosteroid therapy, usually combined with immunosuppressants, is mandatory. Pulmonary arterial hypertension is a classical, but hitherto unrecognized manifestation of SLE which benefits from new exploratory techniques, such as doppler-ultrasonography. At present, its diagnosis rests on data supplied by cardiac catheterization which is generally performed too late, making it irreversible and resistant to all treatments. Some of these pleuro-pulmonary manifestations are probably underestimated and they require new methods of investigation, such as bronchoalveolar lavage or doppler-ultrasonography, resulting in earlier diagnosis and treatment at an accessible stage.