In light of accelerating environmental degradation, the transition to a green economy is an imperative for achieving sustainable development. This study provides a critical analysis of the international legal and institutional framework governing this transition, revealing a significant gap between normative developments and the institutional framework on one hand, and their practical implementation on the other. The transition faces legal obstacles, including reliance on non-binding voluntary commitments and conflicts between environmental obligations and global trade and investment rules. It also reveals a significant financing gap, as financial flows to developing countries continue to lag behind commitments, in addition to technical barriers related to the costs and transfer of technology. The study further uncovers challenges related to social and distributive justice, where the poorest bear the brunt of the impacts and costs, undermining the principle of common but differentiated responsibilities. These obstacles are attributed to deep-seated structural issues, including the prioritization of short-term national interests over the collective good, the fragmented nature of international commitments, the conflict between economic and environmental systems, and a chronic deficit in financing and equity. The study concludes that genuine progress requires a radical restructuring of the international socio-economic contract, and a shift in global governance from establishing ambitious principles to ensuring their binding, fair, and comprehensive implementation. This is essential to transform the vision of a green economy into a practical reality that achieves sustainability and justice for all.