NetZeroCities (NZC) is designed to pursue the ambition of the report from the Mission Board for Climate Neutral and Smart Cities, as part of a broader European ambition to achieve climate neutrality before 2050. This ambition represents a substantial elevation of the degrees of decarbonisation and the timescale for achieving it. For all cities achieving this level of impact is an extraordinary undertaking and would require profound changes in how policies, projects and programmes are advanced by cities, with the direction and support of senior governments. NZC connects and builds beyond established programmes and experimental initiatives. The NetZeroCities consortium is build based on partners? expertise, experience, and access to a very large network of cities of all sizes and maturity throughout Europe. It has an excellent balance of partner typologies, a great geographical coverage allowing presence and activity all throughout Europe, and thanks to that, its approach goes beyond current state-of-the-art. NetZeroCities will create a programme tailored to the specific conditions of each city. All the services and thematic expertise will be aggregated and co-designed through a NZC one-stop-shop Platform and the digital portal and smart repository for impact measurement, capacity building and knowledge/tools dissemination. Cities will benefit from an intensive support relationship of dedicated City Guides to navigate the platform and ensure city needs are adequately understood and addressed. NetZeroCities will support pilots in 30 European cities and, in subsequent rounds of engagement, more than 100 cities to achieving carbon neutrality by 2030 (medium-term) and 2050 (long term) respectively, by developing and deploying an integral approach to support climate-neutral transformation in cities. This will be achieved through the co-design and organisation of services, including the Climate-neutral City Contract as an enabling instrument.