Drawing on theories of institutional evolution, this article contends that despite the centrality of occupationally based social insurance in postwar Korea and Taiwan (and thus the impression of institutional continuity), the welfare state has in fact deepened considerably. The analysis is structured around three distinct eras of social policy reform in Korea and Taiwan: the developmental state, democratic transition, and postindustrialism. The authors contend that during each of these eras, the institutional purposes of social policy were altered to meet certain socioeconomic objectives. New institutional purposes were grafted onto the prevailing social insurance model, changing the outcomes of social policy. The developmental state era was productivist in purpose, democratic reform during the 1980s reoriented social insurance toward universalist and redistributive principles, and the post-1997 era refocused social insurance to meet the imperatives of flexible labor markets, demographic shifts, and economic globalization.