Water, energy, and climate change are intrinsically related to each other but are nonetheless subject to different international legal regimes. The fragmented nature of water, energy, and climate governance represents a challenge for the sustainable management of resources in the energy and water landscape of the 21st century. Regulatory choices in one field can potentially undermine the policy objectives pursued in the other fields. Promoting conventional and unconventional energy production for energy security purposes increases pressure on the availability of fresh water resources and contributes to climate change. Climate change exacerbates the scarcity of water resources, which leads to increasing tensions relating to water access and energy supply in certain regions of the world. Water- and energy-related tensions are particularly acute in Central Asia. Because of its large energy reserves and strategic location in the heart of Eurasia, the Central Asian region is of significant importance for world energy markets. In addition to fossil energy, Central Asia holds large water resources. However, energy and water resources are unevenly distributed in the region, which creates a need for close transboundary cooperation in order to ensure equitable and sustainable access to these vital resources. Despite the mutual benefits of cooperation in Central Asia, governments are reluctant to rely on their neighbors for their water and energy security. States’ refusal to cooperate generates high energy, social, economic, and environmental costs, and poses a serious threat to peace and stability in a region of particular geopolitical relevance. External legal mechanisms are needed to overcome the present political obstacles to transboundary cooperation in resources management. In an effort to overcome the fragmented nature of water, energy, and climate law, this Article examines how international law—in particular the principle of transboundary cooperation—can contribute to addressing the resource management challenges in Central Asia. Additionally, this analysis aims to contribute to the development of international law on transboundary resources management. Based on the Central Asian case study, this Article argues in favor of an integrated approach to water-energy-climate regulation in order to achieve water-energy-climate security in a mutually reinforcing way.