While the amount of cross-national comparative research has continued to grow, especially in Europe, remarkably little attention has been devoted to epistemological and methodological questions. Papers in this book by historians, sociologists, economists and political scientists aim to contribute to his insufficiently explored research topic. Drawn from various European countries, they explain how they construct their research objects. They address the role of languages in comparative research and they all try to reach beyond the opposition between universalism and culturalist relativism or particularism. The authors draw on their extensive empirical knowledge to produce a useful instrument for researchers. Their writing will also find important echoes among practitioners of social policies, who are increasingly confronted with international situations and need models to interpret the practical differences they experience.