Urban challenges such as traffic, air pollution, noise, stress, overcrowding, socio-economic inequalities, food insecurity, excessive waste, ill-health, exclusion, conflict, privatisation of space and impacts of extreme weather, biodiversity loss and the climate crisis are some of the many concerns which urban policy makers are asked to address. In 2018 at a summit of the World Health Organization’s European Healthy Cities Network in Copenhagen, Denmark, hundreds of Mayors committed to taking action on health, wellbeing and happiness in cities.