Nowadays acute limb ischemia (ALI) is still a tremendous complication that may compromise local or general prognosis. Every practician might be able to diagnose this situation in order to transfer in emergency the patient in a vascular unit. The main determinants of outcome of the leg are the severity of the ALI and a prompt treatment. The severity is evaluated according the SCV/ISCVS classification. Patients with a sensitive-motor neurologic deficit are at high risk; they require urgent therapy. The main causes are embolism and thrombosis. In case of classical presentation of embolism, immediate embolectomy will be done under local anesthetic. But this presentation is rare; often the picture is much more complex; the majority of ALI patients are elderly with atherosclerotic vessels. In such situation a team approach is mandatory to decide optimal management. The treatment may combine thrombolytic therapy or aspiration thrombectomy and percutaneous or surgical revascularisation. Finally, atrial fibrillation is now the most common cause of embolism, and appropriate anticoagulation would prevent this complication.