Cement production is a major source of global CO₂ emissions, with decarbonisation challenged by process emissions from limestone calcination. This chapter assesses the potential role of clean hydrogen in decarbonising the sector, primarily through its use as a low-carbon fuel for kiln heating. The analysis finds that while hydrogen combustion can eliminate fuel-related emissions (~40% of the total), it does not address process emissions from limestone calcination (~60%). Technical hurdles, high costs, and infrastructure requirements further constrain its application. Pilot projects demonstrate feasibility only for partial fuel substitution. Consequently, hydrogen is viewed as a potential niche component within a broader decarbonisation strategy dominated by carbon capture, utilisation, and storage (CCUS) and material efficiency, rather than a standalone solution.