This is an excellent discussion of the relationship of constitutional type to the development of tuberculosis in children. The specialist in tuberculosis now feels that the onset, type and course of a case of tuberculosis are markedly influenced not only by the infection and milieu but also by the constitutional factors. The constitution of an individual consists of a number of influences, such as habitus, physiologic properties, reactions, heredity and psyche. Of all these the reaction to various stimuli, exogenous and endogenous, is most important. Two types of children are described, the hypersensitive exudative-lymphatic, and the hyposensitive asthenic type. These are discussed with case illustrations. The booklet should interest physicians engaged in the care of tuberculous children.