In "The Education Gap: Vouchers and Urban Schools" (Brookings, 2002), the authors and their colleagues reported that attending a private school had no discernible impact, positive or negative, on the test scores of non-African-American students participating in school voucher programs in Washington, D.C., New York City, and Dayton, Ohio. But after one, two, and three years in New York City, and after two years in Washington and Dayton, significantly positive impacts for African-Americans were observed. These results came from randomized field trials, which are generally thought to be the gold standard for research on human subjects, and are to be understood as the difference in test scores between those students who used vouchers to attend a private school and those of their public school peers who would have used a voucher had they been offered one. Despite the strength of the evaluation's design, the findings have not been without controversy. Specifically, two secondary analyses of the New York City data have recently been published, with widely diverging results. One study, conducted by a group of distinguished statisticians, John Barnard, Constantine Frangakis, Jennifer Hill, and Donald Rubin (hereinafter referred to as Barnard), has confirmed the study's first-year results but has been virtually ignored in the public media. The other, by Princeton economists Alan Krueger and Pei Zhu, has contradicted their study and twice received favorable coverage in the "New York Times," where Krueger is an occasional columnist. In this article, the authors consider Krueger and Zhu's decision to classify students as African-American if either parent was African-American, how the results change if baseline scores are ignored, and how they change if baseline scores are not ignored. They also discuss the value of randomization. (Contains 3 figures.)