Biodemography, the integration of demographic and biological theory and methods, provides an innovative tool for understanding the impact of aging on health and longevity. This FOA encourageapplications for research combining demographic and life-science approaches for expanding the current understanding of aging/senescence, frailty and mortality. Applications should include evolutionary and life history theories as a framework for investigating individual and population-level factors that underlie changes in lifespan and healthy life expectancy, including sex and population differentials in late-life frailty and mortality.