John E. Franz begins this interview by discussing his early life in Springfield, Illinois, during the Depression. He then describes his undergraduate work at the University of Illinois and his contacts there with Roger Adams, Elliott Alexander, Virginia Bartow, Reynold Fuson, and Carl Marvel. Moving on to his graduate work at the University of Minnesota, Franz contrasts his studies there in physical organic chemistry with his training in practical synthetic organic chemistry at Illinois. Next, Franz discusses choosing to work at the Monsanto Company, rather than DuPont. After describing his first projects, Franz recalls his transfer from the organic chemicals division to the agricultural division, where he worked on synthetic herbicides. This work led to Franz's discovery of glyphosate, a natural plant growth inhibitor that forms the active ingredient in Roundup, an environmentally friendly herbicide that has become one of the most widely used herbicides in the world. He describes the aftereffects of his discovery—the reactions of Monsanto and other companies, and the steps involved in commercial production of Roundup. Franz then examines his later work to understand amine and phosphine compounds as well as plant growth inhibitors. Discussing herbicides in light of current environmental and governmental regulations, he compares Roundup with the more potent herbicides favored by the industry today. Finally, Franz discusses his forthcoming book on the history of glyphosate, his final years at Monsanto, and his retirement.