Governments are increasingly trying to support modernization losers with labor market training but face the challenge that these social investment responses to technological change, globalization, and climate change often perpetuate economic (dis)advantage. Therefore, it is central to better understand the institutional determinants for effective social investment since most current initiatives, especially in coordinated market economies, face the dilemma of whether it is worth connecting them to existing (and eventually outdated) corporatist institutions or whether new policies with fewer institutional preconditions should be prioritized. We argue that social investment policies are especially effective when integrated into corporatist institutions. This is because firms are central intermediate actors shaping both people's experiences with economic modernization and the functioning of social investment policies. Consequently, it is decisive whether social investment policies coordinate firms around strategies that support vulnerable workers during structural change, which is a comparative advantage of corporatism. We test this argument by showing that the success (and failure) of one the world's most praised training schemes, the Danish AMU system, depends on its corporatist capacity to coordinate firm behavior, using full population register data linked to various social surveys. Ultimately, our paper provides a new perspective and unique quantitative evidence for the argument that corporatist economic institutions have a comparative advantage in achieving inclusive outcomes in periods of structural economic transformations.