My scholarly work investigates the ideas and institutions that came together to construct today's Europe; comparisons between the European Union and American federalism; how divisive issues like the authority of the EU affect political parties and democratic representation; and some thorny questions in the philosophy of science and qualitative methodology. My first book, A Certain Idea of Europe (Cornell University Press, 2003, winner of the International Studies Association’s Alger Prize for the best book on international organization in 2003), focused on how certain political principles out-battled others in the construction of the European Union. My second book, How to Map Arguments in Political Science (Oxford University Press, 2007, APSA Giovanni Sartori Prize in Qualitative Methods, Honorable Mention), offers a comprehensive framework for organizing substantive explanations in political science. I have also led three co-edited-book projects, respectively on EU politics (Oxford University Press, 2005), immigration in Europe (Cambridge University Press, 2006), and "constructivist" political economy (Cornell University Press, 2010), and authored an introductory textbook, Introduction to Political Science: How to Think for Yourself about Politics (Pearson, 2nd edition 2020). 

My main current research considers how and why the EU has constructed a "single market" that has removed many internal barriers that persist in the United States. I have a position as Senior Researcher at the ARENA Centre for European Studies at the University of Oslo, and in that capacity received a $1.4 million grant to pursue this project with a team of researchers in Norway, France, Germany and Poland.  In the medium-term future I'm also planning to write a book on philosophy of science tentatively titled Competitive Pragmatism.