The Ethnic Power Relations (EPR) dataset identifies all politically relevant ethnic groups and their access to state power in every country of the world from 1946 to 2005. It includes annual data on over 733 groups and codes the degree to which their representatives held executive-level state power--from total control of the government to overt political discrimination. It also notes when an armed conflict erupted that was fought in the name of a particular group. The ethnic war coding is based on the ACD data-set. The EPR project is a collaborative effort between researchers at ETH Zurich and the University of California Los Angeles.