The electricity industry is undergoing a transformative evolution driven by three overarching trends: decentralization, digitalization, and decarbonization (3Ds). To ensure access to clean, affordable, and reliable energy for all by 2030 - UN sustainable development goal 7 (SDG7) - countries need to repurpose their power market designs to adapt to this transformation and unlock new opportunities. This report provides a fresh global perspective on how to leverage existing designs to effectively mobilize private capital at scale, complementing public investment to achieve SDG7. It draws on a new global database that tracks the evolution of power market structures in all 230 global economies over the past three decades. As countries strive to meet ambitious targets on sustainable energy and access, purposeful power market design will be critical to unlocking the investment needed to meet SDG7.