The purpose of this article is to improve our understanding of data-driven decision-making strategies that are initiated at the district or system level. We apply principal-agent theory to the analysis of qualitative data gathered in a case study of 4 urban school systems. Our findings suggest educators at the school level need not only systemic support but also enough decision-making autonomy to make site-level decisions on the basis of data. Secondly, we found that building expertise and capacity at the school site for data-driven decision-making is necessary but not a sufficient condition for success. Finally, in designing an accountability system, the imbalance in the distribution of information between the central office and the schools must be accommodated. Implications for further research and policy, based on these findings, are also discussed. (Contains 3 tables.)