In a series of 12 pulmonary embolectomies, there were three survivors, none of whom was over 65 years of age. The principal cause of death in the patients who did not survive was cardiovascular collapse of undetermined etiology. Sustained peripheral hypotension was used as the indication for surgical intervention. Embolectomy in other than life-threatening situations is probably unwarranted. Pulmonary arteriography should confirm the diagnosis prior to embolectomy. Cardiac arrest, which occurred in over half of the patients in this series, can be prevented or adequately managed by peripheral cannulization and partial cardiopulmonary bypass prior to thoracotomy. Cardiopulmonary bypass, because it provides adequate time for a deliberate attack, is the modality of choice for the removal of the emboli. The inferior vena cava should be ligated at the time of embolectomy to prevent further embolization.