Following the IPCC Reports from this 22nd year of the XXI st. Century, we realize the unavoidable need and urgency to contribute to the Mitigation of Climate Change, from the Built Environment, as one of the main culprits of the CO2 emissions across the planet. We are looking from the perspective of the increasing occurrence of heat events, the need for better cooling devices, and addressing the heat Island effect in cities, public spaces, and building compounds. But we find that the prevalent strategies refer to the generation of renewable solar or wind energies and ventilation, rather than the prevention of the initial heat gains by solar radiation exposure. The displaced emphasis of our study refers instead to the avoidance of the heat gains provoked by solar radiation. The study was named “the Imperative”, because architects must apply themselves now to contribute to the subject of finding shade from all available perspectives.