Artificial states are those in which political borders do not coincide with a division of nationalities desired by the people on the ground. In this paper, also released in the NBER working paper series, CGD non-resident fellow William Easterly and his co-authors propose and compute for all countries in the world two new measures that show the degree to which a state might be said to have artificial borders. One is based on measuring how borders split ethnic groups into two separate adjacent countries. The other measures how straight land borders are, under the assumption that straight land borders are more likely to be artificial. The authors then show that these two measures seem to be highly correlated with several measures of political and economic success.