Methodologies of international law often have their foundations in ideological positions. Positivism is the best known, and one of positivism’s leading competitors is the “New Haven” or policy-oriented approach , while another is social constructivism , to which a number of prominent international law scholars have subscribed . There are now a number of scholars who identify as Marxist. Their work is summarised by Robert Knox in his comprehensive 2018 entry in the Oxford Bibliographies, “Marxist Approaches to International Law”. He and I both had chapters ten years earlier in Susan Marks’s 2008 International Law on the Left: Re-examining Marxist Legacies. \ud But this is a chapter which does not focus on approaches, or on legacies, but on methodology. In his entry, Robert Knox states that “In Marxist international legal scholarship, one can observe a number of recurring themes. These themes are closely linked to the methodological, theoretical and—crucially—political positions of the Marxist tradition.” This is his only reference to methodology. What if any were the methodological positions of the Marxist tradition?\ud Indeed, it could be said that most international legal practitioners, and many scholars of international law, do without an overt methodology, without any noticeable adverse side-effects.\ud Fortunately, I am able in this chapter to take as my starting point the 2007 entry in the Max Planck Encyclopedia of Public International Law on “Methodology of International Law” by Martti Koskenniemi. Second, I turn to Marx and Engels themselves, who said very little about law, save for a rather pithy 1887 article by Friedrich Engels and Karl Kautsky on “Juridical Socialism” , and, to my knowledge, nothing at all about international law. Indeed, Marx declared famously that if anything was certain, he was not a Marxist.\ud Third, I tackle the most impressive attempt to work out a Marxist theory of law, Yevgeny Pashukanis’s General Theory of Law and Marxism , as promoted and reinterpreted by Robert Knox and China Miéville.\ud Fourth, I turn to the recent work of B. S. Chimni, with his Integrated Marxist Approach to International Law, IMAIL, before concluding with some thoughts of my own.