|Frances Hamilton Arnold|
|Alma mater||Princeton University, University of California, Berkeley, Caltech|
|Notable students||Christopher Voigt, Huimin Zhao|
|Notable awards||Draper Prize(2011), National Medal of Technology and Innovation (2013)|
Frances Hamilton Arnold (born 25 July 1956) is an internationally recognized American scientist and engineer. She pioneered methods of directed evolution to create useful biological systems, including enzymes, metabolic pathways, genetic regulatory circuits, and organisms. She is the Dick and Barbara Dickinson Professor of Chemical Engineering, Bioengineering, and Biochemistry at the California Institute of Technology, where she studies evolution and its applications in science, medicine, chemicals and energy. She earned her B.S. in Mechanical and Aerospace Engineering from Princeton University in 1979 and her Ph.D. in Chemical Engineering from the University of California, Berkeley. There, she did her postdoctoral work in biophysical chemistry before coming to Caltech in 1986.
Her work has been recognized by many awards, including the 2011 Draper Prize and a 2011 National Medal of Technology and Innovation. She was elected to the American Academy of Arts and Sciences in 2011. Arnold has the rare honor of being elected to all three National Academies in the United States - The National Academy of Sciences, The National Academy of Engineering, and the Institute of Medicine. Arnold is a Fellow of the American Association for the Advancement of Science, the American Academy of Arts and Sciences, the American Academy of Microbiology and the American Institute for Medical and Biological Engineering.
A member of the Advisory Board of the DOE-funded Joint BioEnergy Institute and the Packard Fellowships in Science and Engineering, Arnold also serves on the President's Advisory Council of the King Abdullah University of Science and Technology (KAUST). She is currently serving as a judge for The Queen Elizabeth Prize for Engineering, 2013.
Arnold's Caltech research is in green chemistry and alternative energy, including the development of highly active enzymes (cellulolytic and biosynthetic enzymes) and microorganisms to convert renewable biomass to fuels and chemicals. She is co-inventor on numerous patents and co-founded Gevo, Inc. in 2005.
Arnold is the daughter of nuclear physicist William Howard Arnold and grew up in Edgewood, Pennsylvania, a small suburb of Pittsburgh. As a high schooler, she hitchhiked to Washington, D.C. to protest the Vietnam War and lived on her own working as a cocktail waitress at a local jazz club and a cab driver.
- Emanuel Merck Lecture of the Technische Universität Darmstadt, Germany (2013)
- National Medal of Technology and Innovation (2013)
- Charles Stark Draper Prize (2011)
- President Obama Honors Nation's Top Scientists and Innovators 
- Newsmakers, Science, Volume 320, Number 5878, 16 May 2008 
- M. Goho "Cellulolytic Enzymes: Frances Arnold is designing better enzymes for making biofuels from cellulose ."
- 10 Emerging Technologies 2008, Cellulolytic enzymes, Technology Review, p. 52, March/April 2008.
- "Caltech Professor Frances H. Arnold Elected to the National Academy of Sciences". Caltech. 2008-05-05.
- Kharif, Olga (March 15, 2012). "Frances Arnold's Directed Evolution". Bloomberg Businessweek. Retrieved 1 September 2012.
- Hamilton, Walter (July 3, 2011). "Frances Arnold: Career path of a Caltech scientist". Los Angeles Times. Retrieved 1 September 2012.