Burns are entirely particular lesions, which must always be regarded as severe, especially at extreme ages, which affect the body in its entirety. Both the local lesion and the general bodily reaction are dynamic and entail characteristic sequences, which can be anticipated and prevented, in order to reduce the risk of complications and to provide the best possible vital, functional and aesthetic prognosis. The human skin, the largest organ of the body and the most important immune organ, consists of two layers – epidermis and dermis. The action of the thermal agent, irrespective of its aetiology, most commonly affects the epidermis and more or less deep areas of the dermis, depending on the temperature and duration of exposure. In the most severe cases, the dermis is destroyed in its entirety and sometimes, sub-dermic structures are affected as well.