In 2013, Tanzania introduced "Big Results Now in Education", a low-stakes accountability program that published both nationwide and within-district school rankings. Using data from the universe of school performance from 2011-2016, we identify the impacts of the reform using a difference-in-differences estimator that exploits the differential pressure exerted on schools at the bottom of their respective district rankings. We find that BRN improved learning outcomes for schools in the bottom two deciles of their districts. However, the program also led schools to strategically exclude students from the terminal year of primary school. JEL Classification: I21, I25, I28, O15 This open access article is distributed under the terms of the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0) and is freely available online at: http://jhr.uwpress.orgSchool performance rankings based on standardized tests are typically used as the foundation of accountability systems. Such systems are thought to be more effective if school performance is used to sanction or reward schools (Hanushek and Raymond, 2005). However, there are concerns that such "high-stakes" systems can encourage unintended behaviors, including gaming, teaching to the test, and neglecting unrewarded tasks or academic subjects (Baker, 2002(Baker, , 1992 Holmstrom and Milgrom, 1991). Further, political constraints, such as opposition from teachers, make these systems difficult to implement. As a result, the first accountability systems that are implemented tend to be "low-stakes" systems that simply focus on publicizing information about school performance. 1 Although successful low-stakes accountability reforms have taken place in contexts when parents are willing and able to act on the information provided to them (Andrabi et al., 2017;Camargo et al., 2018; Koning and van der Wiel, 2012), these systems may also be effective if they create sufficient reputational pressure for higher-level education administrators or school staff (Bruns et al., 2011; Figlio and Loeb, 2011). But such pressure could be a double-edged sword, encouraging the same distortions and perverse behaviors that are associated with high-stakes systems.In this paper, we study the intended and unintended consequences of a nationwide accountability system implemented in Tanzania in 2012. In response to growing concerns about school quality, the Government of Tanzania instituted a package of reforms that were branded "Big Results Now in Education" (BRN) (World Bank, 2018b). The BRN education program was a flagship reform that was overseen and coordinated by the Office of the President and implemented by the Ministry of Education. It aimed to improve the quality of education in Tanzania through a series of top-down accountability measures that leveraged the political prominence of the reforms to pressure bureaucrats in the education system.A key BRN policy was its school ranking initiative, under which the central government disseminated information about individual primary scho...