The author, with the late Karl Landsteiner, was co-discoverer of the Rh factor. Since then he has been one of the main contributors to this rapidly growing subject, which has affected the practice of medicine in various branches and has been applied to nonmedical disciplines such as genetics, anthropology, and general immunology. In the last 13 years Wiener published 261 papers in various journals, most of them on the Rh factor. From this material he selected 69 articles as representative and most important of his contributions to the subject of Rh. Two brief notes by I. B. Wexler, a frequent co-author with Dr. Wiener, and 10 articles on techniques employed in Wiener's laboratory are also included. The articles are divided into 16 groups, including history, fundamental observations and principles, pathogenesis of fetal erythroblastosis, Rh antibodies, Rh-Hr types and their heredity, nomenclature, anthropological aspects, exchange transfusion therapy of fetal erythroblastosis, MNS