The fibrinolytic system was evaluated in a patient with homozygous protein C deficiency as well as in several members of his family with a partial deficiency of this protein. Before anticoagulant therapy the patient showed skin lesions which quickly disappeared after administration of fresh plasma. After anticoagulant treatment, the propositus suffered two clinical episodes of "ecchymotic" lesions, which were controlled with fresh plasma. The patient has remained free of new lesions and other clinical episodes up to the present date. The fibrinolytic activity of both the propositus and his family was normal. The patient's father showed adequate release of tissue plasminogen activator after controlled physical exercise. According to clinical and analytical data from our patient and his family, it is suggested that, in spite of the preservation of the fibrinolytic system in this case, a localized deficiency in fibrinolysis could exist in view of the clinical behaviour of the skin lesions described.