Projects that focus on genetic controls of aging and longevity, on delay of aging by pharmacological agents or dietary means, or which elucidate the mechanisms by which alterations in hormones, anti-oxidant defenses, or repair processes promote longevity are all within the intended scope of this competition. Projects that focus on specific diseases or assessment of health care strategies will receive lower priority, unless the research plan makes clear and direct connections to fundamental issues in the biology of aging. Studies of invertebrates, mice, human clinical materials or cell lines are eligible for funding. Although preliminary data are always helpful for evaluating the feasibility of the experiments proposed, the emphasis in review will be on creativity and the likelihood that the findings will lead to improved understanding that merits follow-up studies.