Many pediatricians know that in 1948 Clifford Grulee donated his private collection of medical books to the John Crerar Library in Chicago. Comparatively few have had an opportunity to appreciate its quality and scope. With the publication of this catalogue, under the editorial supervision of Herman H. Hinkle, the librarian of the John Crerar Library, and made possible by a grant from the Gerber Baby Food Fund of Fremont, Michigan, one can now take its measure with some accuracy.