Christopher Walsh is a Harvard Medical School professor emeritus who serves as a senior advisor to the ChEM-H Center at Stanford University. He has authored hundreds of papers and books, including the predecessor to this title, Antibiotics: Origins, Actions, Resistance (2003). Dr. Walsh is a member of the U.S. National Academy of Sciences, the U.S. National Academy of Medicine, the American Academy of Arts and Sciences, and the American Philosophical Society and a co-recipient of the 2010 Welch Prize in Chemistry.