This report compares the relative effectiveness of education systems across the developed world. Data come from the Programme for International Student Assessment, Trends in International Maths and Science Study, and the International Adult Literacy Survey. Overall, educational performance in some OECD countries is consistently better than others. A child in Finland, Canada, or Korea has a higher chance of being educated to a reasonable standard and a lower chance of falling far behind than a child in Hungary, Denmark, Greece, the United States, or Germany. The percentage of 15-year-olds judged unable to solve basic reading tasks varies from under 7 percent in Korea and Finland to over 20 percent in Switzerland, Germany, Hungary, Greece, and Portugal. High absolute standards of educational achievement are not incompatible with low levels of relative disadvantage. For OECD overall, the average gap between high and low math scores in the same year is approximately nine times the average progression between one year and the next. Between-school variance in educational performance is much higher in some countries than others. There is no simple relationship between level of educational disadvantage in a country and educational spending per pupil, pupil-teacher ratio, or degree of income equality. (SM)