The New Legal Realist approach to international law builds from a jurisprudential tradition that asks how actors use and apply law in order to understand how law obtains meaning, is practised, and changes over time. The article addresses the jurisprudential roots of the New Legal Realism, its core attributes, and six important components in the current transnational context. In the pragmatist tradition, the New Legal Realism is both empirical and problem-centred, attending to both context and legal normativity. What is new is the rise of transnational activity that gives rise to an enlarged scope of transnational problem-solving through international law in radically new ways across areas of law, and the growth of empirical study of these phenomena. The article concludes by addressing the potential risks of the New Legal Realist approach in terms of scientism and relativism, and it responds to them.