During his 34-year career with Monsanto, Dr. Carpenter played a key role in defining the marketing strategy for herbicides and in developing a variety of new products (such as Roundup) for commercial use. From 1979-94 Dr. Carpenter represented the Chemical Manufacturers Association in U.S. chemical warfare negotiations. For several years he worked for ratification of Chemical Weapons Convention. Currently he is a Trustee of the Chemical and Biological Arms Control Institute.

In 2005, Dr. Carpenter was selected at the recipient of the Distinguished Achievement in Agriculture Award by Gamma Sigma Delta, the Honor Society of Agriculture.