As digitalization reshapes urban landscapes, the concept of "smart cities" evolves from a supply-side, sector-driven approach to one focused on boosting citizen well-being. This paper redefines smart cities as initiatives leveraging digitalization for efficient, sustainable, and inclusive urban services. It delves into a decade of global smart city initiatives, analyzing successes, failures, and policy implications. Exploring diverse definitions and measurement frameworks, it assesses opportunities and challenges of digitalization, highlighting policy implications for OECD governments. Ultimately, the paper advocates harnessing digitalization's benefits to drive inclusive and sustainable urban growth. It proposes pathways for the OECD to address critical policy questions and steer smart city development towards citizen-centric outcomes.