COVID-19, climate change, and the many geopolitical tensions and decoupling that could turn into trade barriers and protectionism, or even regional and global wars, look like just as the preamble of even more disruptions to come. They all share a common theme, reminding us of how weak we are and of humankind’s fallibility (and even existential risk) through history. We discussed at length COVID-19, which came up as a totally unexpected event during the writing of this book. In fact, climate change looks like bringing even greater disruption in the world of cities to come—with the pandemic giving us just a preliminary idea of how hard it will be to deal with this. As stated by The Economist, as economy activity has stalled because of lockdown, 2020 will likely see drops in CO2 emissions of between 4 and 7%. But in order to keep the earth warming target of less than 2 °C, CO2 would need to fall to near zero by 2050—without halting the economies and locking down entire populations but rewiring the first and reshaping the second (The great disrupter 2020). The rewiring of the economy will require a radical redesign of the energy sector and of its global geopolitics, with powerful petro-States of the past giving room to even more powerful electro-States of the future. With clean energy gaining momentum with both investors and end users (and voters) and with interest rates near zero, more and more international politicians are now backing accelerated green-infrastructure conversion plans. The shift from fossil fuel (today accounting for 85% of the energy produced globally) will be evident everywhere and ever so much in the world’s mega cities, which will have to rely on renewable and green energy to provide mobility, heat and air conditioning, and the basic support to commercial and manufacturing sectors working in their extended urban and suburban areas. Energy will also be needed to support services to the person, such as healthcare.