About the Author: PETER J. DUNN, PhD, is Global Green Chemistry Lead for Pfizer. Dr. Dunn has played a key role in the development of commercial processes to make several drugs, including Viagra(TM), Emselex(TM), Revatio(TM), and Sampatrilat. K. K. (MIMI) HII, PhD, holds a Readership in Catalysis in the Department of Chemistry at Imperial College London. Her research focuses on the development of sustainable catalytic processes for organic synthesis. MICHAEL J. KRISCHE, PhD, is Director of the Center for Green Chemistry and Catalysis and Robert A. Welch Chair in Science at The University of Texas at Austin. He is the recipient of the Tetrahedron Young Investigator Award, Humboldt Prize, Presidential Green Chemistry Challenge Award, and ACS Elias J. Corey Award. MICHAEL T. WILLIAMS, PhD, is an independent consultant. Previously, he was an executive director at Pfizer and played a key role in the development and commercialization of many drugs, including Zoloft(TM), Viagra(TM), and Relpax(TM).