The world’s transition from a fossil-fuel-driven society to a future net-zero or negative carbon dioxide emission society will require a significant scale-up of Power-to-X technologies to capture and convert CO2 to low carbon intensity fuels and chemicals. The deployment of Power-to-X technologies at gigawatt scales necessary to impact on CO2 emissions and replace existing fossil-fuel-dependent processes will require vast quantities of raw materials and minerals. Many of the materials required in Power-to-X systems, such as rare earth metal yttrium and iridium, differ from those used to construct and operate petroleum-hydrocarbon-based processes for the last 100 years. Thus, electrolyzer manufacturers and mineral producers face significant challenges in matching supply to the growing demand. In this Perspective, we identify critical materials needed for Power-to-X electrolyzers and analyze the impacts and risks of these materials’ existing global supply chains. We then provide an overview of methodologies for Environmental Life Cycle Assessment (LCA) and Social Life Cycle Assessment (SLCA) that we encourage scientific communities to adopt early in the research process to evaluate the multidimensional socio-environmental impacts throughout a product’s life cycle, from raw material extraction and processing to manufacturing, use, and end-of-life disposal. We advocate that life cycle thinking is crucial for the informed, just and ethical development of disruptive technologies and systems such as Power-to-X technologies.