When the history of immunology in the twentieth century is written, the decade of the 1960's will, in all probability, stand out as the period of greatest advance in the development of molecular immunology. It is appropriate and useful, therefore, that a schol arly and integrated presentation of this progress should be made available in English. The translation of Dr. Nezlin's "Biochem istry of Antibodies" from Russian admirably fulfills this need in the form of a scientific monograph directed to medical and biolog ical scientists. The appearance of this monograph also serves to emphasize the conceptual unification of diverse immunological phenomena which has emerged from progress in molecular immunology. This unity is a consequence of the key role played by the antibody mol ecule (either in solution or cell-bound) in every biological process properly described as immunological. Indeed, immunology as an independent natural science can be described as the study of the structure, interactions, and biosynthes is of the antibody molecule.