Most countries in sub-Saharan Africa have not implemented testing of children’s learning that can be benchmarked regionally or globally. In contrast, in the last two decades, almost all countries in Latin America have participated in regionally and globally benchmarked testing initiatives. Our analysis of the political economy of cross-national learning measurement in Latin America suggests that policymakers perceive the risks of exposing their education system’s performance by joining cross-national assessments, but they also value the quality of the data generated, the strengthening of domestic technical capacity, and the political benefits in using comparative results to argue for reforms or to advertise progress. We document that in Ecuador and Peru cross-national tests played an important role in both stimulating and justifying reforms that have produced major improvements in learning. In sub-Saharan Africa, no cross-national test has been implemented as consistently or widely as the Latin American regional test. The context in Africa makes regional cooperation on cross-national testing more daunting—countries are poorer and more linguistically diverse than in Latin America, raising the relative costs of developing and administering cross-national tests. The experience of Latin America suggests that a coordinated and efficient application of resources in implementing cross-national tests in Africa, on the part of countries and with support of the international community, could help build countries’ national capacity, strengthen focus on learning, support better research, and help diffuse reforms that raise learning.