This chapter discusses the Ethnic Power Relations (EPR) family of datasets. These resources are available through the online data portal Growup (Geographic Research On War, unified platform), which is provided by the International Conflict Research (ICR) group at ETH Zürich (see https://growup.ethz.ch" xmlns:xlink="https://www.w3.org/1999/xlink">https://growup.ethz.ch). This platform allows users to gain easy access to data on ethnic groups’ political power and conflict behavior around the world from 1946 through 2009. After describing the motivations, development, and design of the data and the portal, we turn to their research applications.