Chronic critical ischemia of the lower limb (CCLI) is the most severe form of peripheral arterial disease. This terminology reflects the need to compare treatments based on an accurate and objective description of the clinical cases rather than subjective items like limb threatening ischemia or intervention for limb salvage. At the stage of CCLI the prognosis is very poor with a high risk of major amputation or disability or death. This highlights the importance of a precise clinical evaluation (including an hemodynamic reading of the clinical assessment of the foot) and of the use of the appropriate diagnostic tools to confirms CCLI diagnosis. This approach is invaluable for the correct stratification of the amputation risk.