This book presents the results of research on the effects of vouchers on African American students' achievement in Washington, DC, New York, New York, Dayton, Ohio, and San Antonio, Texas. At the conclusion of a 3-year evaluation, test scores of African American students in New York City's privately funded voucher programs were substantially higher than test scores of comparable public school students. The difference was large enough to erase almost half of the achievement gap between African American and white students. Scores of students of other ethnic backgrounds in New York City public and private schools did not differ significantly. In Washington, test scores of African American voucher students were 9 percentile points higher than scores of African American public school students after 2 years, but no different after 3 years. In both cities, private school parents were much more satisfied with their children's schools than public school parents. Combined data from New York, Dayton, and Washington showed that African American voucher students scored, on average, three percentile points higher than their public school peers in year 1, six points higher in year 2, and seven points higher in year 3. Study data are appended. (SM)