This book contains 28 chapters representing the opinion of key vascular specialists. It covers a wide spectrum of definition and criteria of critical limb ischemia (CLI), its pathophysiology, epidemiology, assessment, and therapy. Objective criteria, which are associated with the definition of CLI, have been the source of many debates and, therefore, their disadvantages and limitations are presented and alternatives and recommendations are suggested. Present-day medical treatment of CLI includes spinal cord stimulation, antiplatelet drugs, defibrinating agents, vasoactive substances, and prostanoids. Therapies of choice, such as distal bypass surgery for extensive arterial disease, and alternative procedures are also surveyed. Clinical and surgical specialists concerned with endovascular and surgical intervention will benefit from this engaging treatise that stretches from general to specific medical conditions of CLI, quality of life, long-term morbidity and mortality, and the role of primary amputation.