Contributor(s): Professor Dani Rodrik | Capitalism needs to be reinvented for a new century in which the forces of economic globalization are much more powerful than before. Just as Adam Smith's minimal capitalism was transformed into Keynes' mixed economy, we need to contemplate a transition from the national version of the mixed economy to its global counterpart. We have to imagine a better balance between markets and their supporting institutions at the global level. Sometimes, this will require extending institutions outward from nation states and strengthening global governance. At other times, it will mean preventing markets from expanding too much and going beyond the reach of institutions that must remain perforce national. Dani Rodrik is Rafiq Hariri Professor of International Political Economy at Harvard University and teaches in the School's MPA/ID Program.