Professor Daniel Eisenstein studies cosmology and extragalactic astronomy with a mix of theoretical and observational methods. His dominant focus over the last decade has been on the development of the baryon acoustic oscillation method to measure the cosmic distance scale and study dark energy. Dr. Eisenstein received his Ph.D. from Harvard University in 1996 and then held postdoctoral positions at the Institute for Advanced Study and the University of Chicago. He was on the University of Arizona astronomy faculty for 9 years before moving to his current position as a professor of astronomy at Harvard University in 2010. He has been active in the Sloan Digital Sky Survey since 1998 and is currently the Director of SDSS-III. He is now serving as chair of the National Science Foundation Astronomy Portfolio Review committee. He has been a member of numerous other scientific collaborations and national committees.