[영문]The paper describes how changes in the inequality of lifetimes have contributed to changes in the social distribution of welfare. I address the following questions: How can we measure inequality of lifetimes? How has this kind of inequality changed over time? How is this inequality related to increased longevity? How do these trends differ across and within countries? Unequal longevity was once a major source of social inequality, perhaps even more important in some sense than income inequality, for a long time. But over the last century, this inequality has declined drastically in high-income countries and is now comparatively trivial.