The FDA is prepared to lead the way in strengthening regulatory science.But this will require collaborations and partnerships with academia, industry, and other government agencies. With an advanced field of regulatory science, new tools, including functional genomics, proteomics, metabolomics, high-throughput screening, and systems biology, can replace current toxicology assays with tests that incorporate the mechanistic underpinnings of disease and of underlying toxic side effects. This should allow the development, validation, and qualification of preclinical and clinical models that accelerate the evaluation of toxicities during drug development. The FDA is focused on research efforts (PACES), which will explore existing patient data to identify subgroups for whom the benefit to risk is greatest as well as how to leverage new design strategies for estimating treatment effects in subpopulations and improving trial designs.