No international regime operates in complete isolation from other regimes and the wider body of international law. Conflicts and tensions, but also potential synergies, are inevitable consequences of regime coexistence. Such interactions are particularly apparent in the case of the climate regime, which is analysed in this article in relation to the international law on biodiversity protection and free trade.

Born into the wider body of international law, the climate regime needs to be understood in light of pre-existing regimes. By drawing on the current debate about fragmentation in international law, this article highlights challenges for international lawyers and policymakers in navigating the relationship between the climate regime and the biodiversity regime, and the relationship between the climate regime and the multilateral trading system.

This article concludes that a narrow focus on conflicts misrepresents the multifaceted nature of climate change and precludes an adequate jurisprudential understanding of the relationship between the climate regime and other regimes. An improved understanding, particularly with respect to interactions with the biodiversity regime, requires a broadening of the debate that takes account of the institutional aspects of these relationships that may allow enhanced political cooperation and coordination.

Further, international law, and in particular the emerging concept of systemic integration, has the potential to make a positive contribution to the climate-trade interplay.