The editor of this series, Dr. S. Z. Levine, is to be congratulated on his perceptive selection of topics which are in need of review at this time, and for his wise choice of authors to take on these assignments. Such a group of reviews as are contained in this volume are essential for anyone who strives to maintain a broad grasp of the subject matter of pediatrics. The same well-balanced assortment of material which has characterized this series of reviews is maintained in the present volume. It is fortunate that there is so little duplication in the subjects treated in the several books now available each year containing reviews of topics in pediatrics.