Hydrogen is rapidly becoming a foundation of the global green energy transition, offering a clean fuel to decarbonize sectors like heavy industry, aviation, and shipping. Green hydrogen— produced using renewable electricity—is gaining traction worldwide. However, freshwater resources needed for traditional electrolysis are increasingly scarce. This makes seawater— covering over 96% of the Earth’s water—a highly attractive and abundant alternative for hydrogen production. Producing hydrogen directly from seawater avoids the need for costly and energy-intensive desalination, but it brings technical challenges such as corrosion, biofouling, and interference from salts and impurities. New technologies are emerging to address these issues, including specialized catalysts, impurity-tolerant membranes, and Bipolar Membrane Water Electrolysers (BPMWE) that can operate efficiently with seawater. When powered by renewable energy, seawater electrolysis presents a scalable and sustainable pathway for clean hydrogen production, particularly in coastal and freshwater-stressed regions.