The report first evaluates the dynamics between urbanisation and green spaces, and second, explores the potential of green spaces to boost the resilience and sustainability of cities in the future. The results show that as urban agglomerations become larger and more compact, green spaces disappear, exacerbating their vulnerability to climate change and deteriorating liveability. However, building taller buildings (i.e., growing vertically), offers a way for cities to grow whilst minimising loss of green space. Results show that more green space can boost sustainability by significantly lowering air pollution in African cities, which could be vital for public health in the future since outdoor air pollution is rising.