In the Institute for Green Oxidation Chemistry, we develop oxidation catalysts with useful lifetimes via an iterative design process in which oxidation-sensitive ligand groups are identified and replaced. The process has led to catalysts with greatly enhanced stability toward oxidative and hydrolytic degradation. The iron catalysts described herein can be comprised exclusively of biochemically common elements. They are efficient and selective peroxide activators for many areas of technology. They are water-soluble and are effective in minute quantities (nanomolar to low micromolar) over a broad pH range. Various green chemistry applications are sketched.