The association of ischemic cerebrovascular lesions with livedo reticularis is known as Sneddon syndrome. It affects young subjects, primarily women, and its neurological manifestations are TIAs, ischemic stroke, progressive dementia and epileptic seizures. Its etiopathogenesis has still to be clarified. Some authors have associated it with an antiphospholipid antibody syndrome. Recently it has been assumed that a defect in blood coagulation may be involved in its pathogenesis. Here we report a case in which both an increase in coagulation factor VII activity and a deficiency in free protein S were documented.