In this article, the authors develop an argument about the global forces that have led to the explosive growth of national educational assessment and international testing. In particular, the authors argue that the international acceptance of testing comes from key ideological forces in the world polity that are associated with the accelerating globalization of national and international cultural, economic, and political structures. As they develop and warrant this argument, the authors also qualify it by pointing out that national adaptations to this larger world culture may vary depending on the presence and capacities of international organizations and regional associations that act to mediate and adapt these changes to conditions in individual countries. In addition, the authors consider the effects of subnational movements in introducing pressures for change that may favor more national assessment. (Contains 1 figure and 19 footnotes.)