He spent 32 years on faculty at the University of Wisconsin-Madison as a faculty member studying the cytoskeleton, becoming a professor in 1968 and chair of Molecular Biology from 1980 to 2000. In 2000, he moved to Northwestern UniversityFeinberg School of Medicine where he was the Leslie B. Arey professor of cell and molecular biology, distinguished investigator in the Feinberg Cardiovascular Research Institute, and associate vice president for biomedical research.[3] He was named CEO and director of the Marine Biological Laboratory in 2006, and retired in 2012 at age 70.[4][5]