At the foundation of protecting living things from toxicological impacts is the concept of ADME (absorption, distribution, metabolism, excretion).  By understanding the molecular parameters that control the stages of ADME, substances can reduce a chemical’s bioavailability—its ability to access a biological system. The insights from pharmaceutical research in trying to maximize bioavailability have provided intellectual tools that can be used in all aspects of the chemical enterprise in thoughtful design for hazard reduction.