I would like to thank Daniel Nexon for taking the time to read, reflect, and comment on the article ‘Theorising the International System: Perspectives from Historical Sociology’. His comments are astute, pertinent and challenging. I would also like to thank the editors of the Review of International Studies for offering me space to reply to Nexon's comments. Nexon clearly wishes that I had written a different article. However, although I think that the article he has in mind is one that should be written, I had different intentions in mind. Nexon is clearly doing a big service to International Relations scholars by introducing them to relational sociology, but this was not what I set out to do. I will start therefore with some comments on my intentions in writing the article. I will then offer some points of clarification. Finally I will address Nexon's major criticisms of the article: my failure to acknowledge relational sociology and my critique of the analysis of international systems in the works of Tilly and Mann. My overall argument will be that the dichotomy that Nexon offers between neofunctionalism and relational sociology is not as straightforward as he suggests. He acknowledges this in his final footnote, and it is a point also conceded by Emirbayer in the article that Nexon primarily draws upon. Furthermore, on this point, I think that we share more common ground than Nexon would wish to acknowledge. However our positions on structures are radically different. On this point our differences are, I believe, irreconcilable. What I will attempt to argue is that there are fundamental differences between material and ideational structures which makes it difficult to analyse them cumulatively.