Ruth Ley received a BA in Integrative Biology from the University of California at Berkeley, a PhD from the University of Colorado, Boulder, and then received an NRC-NASA Fellowship for post-doctoral work with Dr. Norman Pace at CU Boulder. She moved to Washington University School of Medicine to work with Dr. Jeffrey Gordon on the human microbiome in 2004. She was named an Instructor in 2005 and a Research Assistant Professor at Washington University School of Medicine in 2007. In July 2008, Ley joined the Department of Microbiology at Cornell University as an Assistant Professor, and in 2013 became an Associate Professor with tenure in the Department of Molecular Biology and Genetics. She is currently the Director of the Department of Microbiome Science at the Max Planck Institute for Developmental Biology in Tübingen (2016). Since 2018 Ley is a speaker for the Center of Excellence award “Controlling Microbiomes to Fight Infections” with the University of Tübingen.