During the postwar period, Japan, Taiwan and South Korea emerged as industrial and democratic exemplars in the East Asia region. A less well-known story is of their equally remarkable achievements in social policy reform and the formation of welfare states. Section 1 of the Element provides an overview of welfare state deepening in Japan, Taiwan and Korea and an account of why and how the developmental states institutionalized the social insurance model. Section 2 examines the drivers of social welfare universalization in Japan, Taiwan and Korea, notably the importance of democratization. Section 3 focuses on emerging challenges to the East Asian welfare state and how it has adapted. Though Japan, South Korea and Taiwan evolved their welfare states in a distinctive way historically, the current challenges they face and their responses have converged with other developed, post-industrial democracies.