Douglas C. Rees is an American biochemist, biophysicist, and structural biologist. He graduated from Yale University with a bachelor’s degree in 1974 and received a Ph.D. in biophysics from Harvard University in 1980. In 1982 he went to the University of California, Los Angeles. In 1989, he became a professor of chemistry at Caltech and is currently the Roscoe Gilkey Dickinson Professor of Chemistry. From 1997 onwards, he has been an investigator at the Howard Hughes Medical Institute. He is interested in the structure and function of metalloproteins and membrane proteins that participate in energy transduction or conversion pathways in biological processes. In 2015, he received the FA Cotton Medal, and in 2020, he was awarded the Gregori Aminoff Prize. He is a member of the American Academy of Arts and Sciences, the National Academy of Sciences, and was a Sloan Research Fellow.