This paper discusses the adoption of the Paris Agreement, which took place in a challenging and tense context, requiring significant innovation and resourcefulness from negotiators. To ensure the participation of all states, this new treaty underwent adjustments in both structure and substance compared to its predecessor, the Kyoto Protocol. While the Paris Agreement may initially appear to emphasize flexibility, a closer examination reveals it to be a well-balanced compromise between advocates of a flexible accord and proponents of a more binding one. This study explores the agreement’s form, highlighting a nuanced blend of hard and soft law in Section I. In terms of substance, it argues for an equally nuanced combination of bottom-up and top-down approaches, as discussed in Part II. The Paris Agreement thus represents a notable evolution in the way states engage with international law.