This article sets out the major tenets of new materialism and maps out its implications for international law. It considers what new materialism might offer for those of us working within international law in the way of new insights, resources, practices or politics. It first sets the contours of new materialism within the broader material turn. It then elaborates three main tenets of new materialism’s methodology, theory, and ontology: its attention to matter in its physicality; the embedded and entangled subject; (...) and the vitality or agency of objects. The article focuses on how new materialist work might help us to understand, first, subjectivity and second, power and accountability in international law. It concludes that new materialist approaches offer important and compelling insights, working against entrenched categories and structures that continue to perpetuate or excuse violence and harm in international law’s doctrines and practices. These insights provide resources for rethinking power and subjectivity, and the role these play in international law. However, those of us working to consider how we can respond to pressing crises of justice and coexistence within international law may find new materialism most powerful when brought into relation, and deep conversation, with more structural methodologies. Notably ‘older’ materialisms grasp embedded power relations and deep-rooted systemic harms in more concrete ways. This is, the article concludes, a conversation that international law scholars are well placed to contribute to, deepening both ‘old’ and ‘new’ materialist insights for international law. (shrink)