This open access book sheds light on hydrogen energy transition on a global scale. Interest in hydrogen and its role in the globally ongoing energy transitions is surging. At issue are profound technological and infrastructural shifts in global fuel production and trade, with new producers emerging along with competition between different types of hydrogenrenewable, low-carbon and fossil fuel-based, and derivative fuels such as methanol and ammonia. At the same time, this technological and infrastructural shift also raises wider questions on how market actors and their host states interact, how energy policies develop in first-mover states, along with the effects vis-à-vis international interaction, institutions and patterns of regional and global order, and ultimately, what are the consequences for the planet. In other words, considering hydrogens role in energy transitions directs us towards some fundamental questions on how the geopolitics of energy evolves. This book addresses precisely this problem. It sheds new light on the interests driving the state and market actors in several country level case studies, their regional and global interactions, involving special themes such as the fate of fossil fuel producers, as well as implications for energy security, energy diplomacy and energy transitions.