This scientific history of Rh-isoimmune hemolytic disease deals with a clinical disease that is packed with emotion and a series of discoveries that progress from initial delineation of the disease through development of a successful treatment to a simple method of prevention, all within a period of just two generations. Mr. Zimmerman tells the story nicely by orienting all the earlier history around the final series of investigations in the 1960s that produced effective prophylaxis. At that time, a group in Liverpool, England, led by Drs. Finn and Clarke, and a group in New York City, Drs. Freda, Gorman, and Pollack, independently developed the concept of using anti-Rh antibody injections to prevent sensitization of Rh-negative mothers. The English workers arrived at the idea from the basic science approach, when the studies they were doing to answer purely genetic questions produced the clue that led them to this idea. The American