Paul J. Kaesberg, age 87, died on Friday, Dec. 24, 2010, surrounded by his family at his home in Madison. In 1948, Paul received his Ph.D. in physics from the University of Wisconsin-Madison. He then joined the faculty of the University of Wisconsin-Madison, rising to become the W.W. Beeman Professor of Biochemistry. Paul was a fellow of the American Academy of Microbiology, and a past president of the American Society of Virology. He received international recognition for his pioneering research on small viruses. In 1991, Paul was elected to the National Academy of Sciences. He was also honored by Professor Paul Ahlquist, who took the title Paul Kaesberg Professor of Biochemistry.