After receiving BS and MS degrees from the University of Washington in Seattle, I entered its new medical school in 1947, receiving an MD degree in 1951. After internship and residency, I obtained a 2-year postdoctoral fellowship in hematology under the guidance of Dr Clement Finch. The last 6 months of the fellowship were spent in London, England, at Dr Patrick Mollison's Blood Transfusion Research Unit. There I met and worked with Marie Cutbush (later Crookston) who has been a long-term friend. On returning to Seattle, I joined the faculty of the medical school and became the associate director of the Puget Sound Blood Center. There, I supervised the blood typing and cross-matching laboratory, introducing methods I had learned in London and measuring the effectiveness of various cross-matching procedures. My own research was largely directed toward human genetic polymorphism, and I wrote a textbook published in 1969, describing the biochemical structure, function, inheritance, and geographic distribution of the genetic markers. Subsequently, I discovered that 2 forms of inherited immunodeficiency disease were due to deficiencies of the enzymes adenosine deaminase and purine nucleoside phosphorylase. In 1979, I became the director of the blood center and was shortly afterwards elected to the National Academy of Sciences. I retired in 1987 and have spent most of the intervening years relearning to play the violin and exploring the wonders of chamber music.