24 cases of axillary-subclavian venous thrombosis were studied according to the etiology: "intrinsic" thrombosis secondary to alteration of the endothelium (7 cases), "extrinsic" thrombosis secondary to compression at the level of the thoracic outlet (4 cases), "combined" thrombosis following a complex treatment of breast cancer (3 cases). The frequency of these thromboses, undoubtedly underestimated, seems low as compared to that of venous thromboses of the lower extremities. The frequency of pulmonary emboli is 8%. The treatment is limited to anticoagulants in case of intrinsic or combined thrombosis. In the third type, decompressive surgery is necessary, especially if there are abnormalities of the cervico-dorsal junction or associated neurological or arterial disorders.