Analyses have been made of 27 cases of acid and alkali injury seen during the past 5 years. These injuries behaved differently from thermal injuries. They were generally less extensive and mainly involved the head and neck, upper trunk and upper extremities. Initial clinical assessment is difficult and, irrespective of depth, the surface appears dark brown, becoming black later. Even when superficial these burns do not show blisters. Burn wound sepsis is not usually seen until week 2 postinjury and eschar separation is delayed. Invasive sepsis is uncommon. Ocular involvement is common and in severe cases leads to loss of vision. These cases are most suitable for eschar excision and grafting soon after admission because of the limited area of the burn, the greater depth of injury and the delayed onset of burn wound sepsis.