These writers review the literature on the theory of allergy and describe some experiments of their own on the production of bronchial asthma in guinea pigs. They argue that allergy is simply a special type of antigen-antibody reaction of a predominantly local nature. They are satisfied that the product of this reaction which causes the symptoms is a histamine-like compound. For therapy, the usual measures—specific desensitization, calcium preparations, atropine preparations and epinephrine-like substances—are deemed to be rational. The monograph is more a review than a presentation of novel ideas.