“Concrete is an invention as transformative as fire or electricity. It has changed where and how billions of people live, work, and move around. Concrete is the skeleton of the modern world, the scaffold on which so much else is built. It gives us the power to dam enormous rivers, erect buildings of Olympian height, and travel to all but the remotest corners of the world with an ease that would astonish our ancestors. Measured by the number of lives it touches, concrete is easily the most important man-made material ever invented.”