Critical limb ischaemia is a term used to describe ischaemia of such severity that in absence of successful revascularization the limb will require a major amputation. The assessment of such cases through clinical examination of patients to detect if there is tissue loss, ulcer or not. In addition the patients arterial trees assessed by arterial duplex and angiography to detect distal runoff that the revascularization will be done on it. Preoperative assessment of these patients is very important to predict the risk of operation if it is high moderate or low risk by doing ECG. Echocardiography in addition to the routines labs. The management of CLI is including: Non-surgical treatment of lower limb ischemia. Endovascular therapy. Surgical revascularization. Otherwise amputation will done and it may be life saving for the patient. However, the decision in such patients by revascularization versus primary amputation is still controversial and there is a great argument between the two decision depending on the criteria mentioned above.