Gangrene is the macroscopic death of the tissues with superadded putrefaction. This chapter describes causes, clinical features, clinical types, spread of gangrene and its treatment in general. Individual causes of gangrene and diseases affecting arterial system are described in detail with the help of clinical photographs, boxes, flow charts and case summaries. Surgery for chronic lower limb ischemia, embolism, Buerger’s disease, Raynaud’s disease, Raynaud’s syndrome, cervical rib and thoracic outlet syndrome, etc. are the topics discussed in this chapter. Drugs causing gangrene like ergot preparations and intra-arterial drugs, venous gangrene, traumatic gangrene, physical gangrene, chemical gangrene, infective gangrene, diabetic gangrene are also outlined.