How can party system design contribute to managing ethnic relations? This thesis investigatesthe relationship between party system design and the type of nation-building efforts pursuedin a country. More specifically, whether a country allows ethnicity to be a source of politicalmobilization or not and how that relates to nation-building policies having an assimilating ora multicultural character. Departing from the debate between the integrative approach and theconsociational approach, theories of institutional design, the thesis theorizes that countriesbanning ethnic political parties are pursuing civic nationalism and should therefore havenation-building policies with an assimilating character. On the other hand, it theorizes thatcountries that do not restrict parties to form on ethnic basis will have multiculturalnation-building policies, striving for a multicultural nationalism. Using a ‘most similarsystems design’ the study investigates the nation-building policies in Kenya and Nigeria, twosimilar countries with different party system designs. It mainly investigates education policiesto look for indicators of assimilating and multicultural nation-building. Taken together, theresults show that national unity and integration is an overarching goal which overridescultural recognition in both cases. The correlation between party system design and type ofnation-building policies show to be weak since the two countries have very similar policies.However, some nuances in means to achieve national unity are found.