IgE levels in the serum of individuals with burns were sequentially measured and compared to IgE levels in normal control blood donors. Following a burn, the levels of IgE protein showed a significant, although modest, increase, usually evident between days 14 and 22. In an occasional patient, the IgE levels rose by as much as five times in value during this period. Because of the complexity of the clinical situation associated with the burn patients, we cannot ascribe these elevations of IgE to the burn per se, but must consider the possibility of other factors, especially those involved in the treatment of the burn as well as the infection. The magnitude of the elevation of IgE in the burn patients (geometric mean = 272 ng/ml) was considerably lower than the magnitude of the elevations seen in atopic dermatitis and generalized neurodermatitis (geometric means = 2265 and 2071 ng/ml, respectively). Thus simple trauma to the skin is not a sufficient explanation for the elevated serum IgE levels in atopic dermatitis and generalized neurodermatitis.