"The Child in Health and Disease" is based on the thesis expressed in the preface". . . to correct the emphasis on investigation (which) has led to . . . a feeling of complacency when the practical side of pediatrics has come to the fore. We are prone to forget that the value of medical investigations depends upon its practicable application as the final test of its usefulness." This ambition is most commendable, since the science of medicine has made such tremendous strides during the past 2 decades.