Bill received a B.A. from Pacific Lutheran University and attended medical school at the University of Washington. He participated in the Epidemic Intelligence Service (EIS) of the Centers for Disease Control and Prevention (CDC) between 1962 and 1964. He entered the Master of Public Health program at the Harvard School of Public Health where he received his M.P.H. in 1965. He is a well-know epidemiologist who is credited with devising the global strategy that led to the eradication of smallpox in the late 1970s.