The Geneva Cities Hub (GCH) aims to better connect cities, local and regional governments to the International Geneva ecosystem. Connecting all relevant stakeholders, GCH is a platform that pursues 3 main objectives: Facilitating participation of cities and their networks in relevant multilateral processes and bodies. Facilitating partnerships between cities, their networks and Geneva-based international organizations and other entities. Urban mainstreaming by providing a space to discuss urban issues and enhance the visibility of the urban work of Geneva-based actors. Urbanization is a defining trend of the past decades, and it will define our future. Today, more than half of the world’s population lives in cities and by 2050, 68 % of the world’s population is projected to be urban. In comparison, 30 % of the world’s population was urban in 1950 (cf. UN World Urbanization Prospects: The 2018 Revision). New cities have thus emerged, and cities become bigger day after day. This trend has affected the way people live, work, think and thrive. And it should also impact the way diplomacy works and international relations are conducted. Cities become an actor more and more important for te health of the population (regulation of traffic, greening the citiey, solidarity with fragile population...).