Harold F. Walton joined the staff of the University of Colorado in 1947. His research interests in ion exchange date from 1938 when he went to work for the Permutit Co. as a research chemist; from there he went to Northwestern University in 1940. He obtained the BA and DPhil degrees at Oxford University. He Is the author of three textbooks on inorganic and analytical chemistry and coauthor with William Rieman III of "Ion Exchange in Analytical Chemistry" published in 1970. He has contributed chapters on the physical and analytical chemistry of ion exchange to several cooperative works. In 1961 he was chairman of the Gordon Research Conference on Ion Exchange. Dr. Walton spent the 1966-67 academic year and half of 1970 as a Fulbright visiting professor at the University of Trujillo, Peru. He Is a member of the Advisory Board of Analytical Chemistry.has chapters on ion exchange in nonaqueous and mixed solvents by Marcus, on ligand-exchange chromatography by Walton, and on liquid ion exchange technology by Kunin; Volume 5 has accounts of inorganic ion exchangers by Clearfield, Nancollas, and Blessing; of ion exchange in elemental analysis by Strelow; and on pellicular ion exchange resins by Horvath. A good short account of ion exchange in analytical chemistry is that by Inczedy in the Chemical Rubber Publishing Company's review series (A6). The International Union of Pure and Applied Chemistry has published the report of a committee on ion-exchange nomenclature, consisting of O. Samuelson, E. Bayer, and F. G. Helfferich (A7).In the Russian language, two books on ion exchange have appeared (A9, A 28). Both books were reviewed in the Russian Journal of Analytical Chemistry (Zh. Anal. Khim.). Another significant Russian book is that edited by Sladkov (A 29), which has a chapter by Davankov, Rogozhin, and Semechkin on ligand-exchange chromatography and another by Rogozhin, Davankov, and Peslayakas on the chromatographic separation of optical isomers. Reviews on chelating ion exchangers (A 23) and complex-ion formation in exchange resins (A27) have also appeared. A paper by Gurvich (288) describes the use of organic complexing agents incorporated into absorbants like charcoal.A German review (A20) is aptly titled "Ion Exchangers -Active Polymers." Recent progress in ion-exchange chromatography is reviewed in Japanese (A 14). An English-language book reflecting the author's own research and interest is that by Muzzarelli (A22).The latest volume of "Chromatographic Reviews," now published as an integral part of the Journal of Chromatography, includes two chapters on a very timely topic, the