Achieving global climate goals requires addressing whole life carbon emissions of buildings, encompassing both operational and embodied carbon-the often-overlooked emissions generated before residents even set foot in their buildings. This OECD report, Zero-Carbon Buildings in Cities: A Whole Life-Cycle Approach, brings whole life carbon to the forefront of the decarbonisation agenda. Based on a global survey of 18 countries and cities, it highlights best practices, proven strategies, and actionable insights for policy makers at all levels. By bridging a critical gap in sustainable building policies, this report equips countries and cities to accelerate the transition to zero-carbon buildings and build a more sustainable future.