Following Hurricane Katrina in 2005, a small, mostly unelected group of White people orchestrated the transformation of the New Orleans public school system, whose students were almost exclusively poor and Black. Under the new regime, the state assumed authority over most schools. Officials then transferred the operation of nearly all of them to nonprofit charter school organizations, which ran them according to terms specified in performance-based contracts with the government. Local and state authorities eliminated geographically based attendance zones, enabling families to apply to any school in the city. The government also gained the power to close, take over, or change the management of schools that did not meet their performance targets, and a robust nonprofit sector developed to handle many administrative tasks that the school district previously managed. Lastly, schools gained greater authority over formerly unionized teachers, who lost their jobs and collective bargaining agreement after the storm.Economist Douglas N. Harris reports that these reforms shifted the composition of the New Orleans teacher corps from three-quarters Black to majority White (with many of the newcomers hired through organizations such as Teach For America), maintained segregation, and diluted the input that voters in the majority Black city had over their public schools. But Harris demonstrates that the reforms also "were successful in improving every measurable outcome, from test scores to college graduation" (p. 80). Harris's rigorous analyses show that by 2015, "the reforms increased test scores by 12-15 percentiles, high school graduation by 3-9 percentage points, college entry by 8-15 percentage points, and college graduation by 3-5 percentage points" (p. 87). These gains were notable because many people viewed New Orleans as one of the nation's most troubled school districts prior to 2005. Among the many questions these findings raise, however, is whether these academic improvements justified the social, political, and economic costs.Harris does not answer this question directly. Rather, he seeks to understand what drove academic improvement and to identify the lessons New Orleans provides for public school reform nationally. Harris tests a number of factors that market theory-and school choice advocates-highlight as potential drivers of academic gains in a market-based system. These include the autonomy schools gained to hire and fire teachers, the competition that emerged between schools for students and resources, the ostensibly expanded choices that families received to select schools, and the government's new role as an authorizer and contractor with the power to shutter, take over, or transfer the management of low-performing schools.