For millennia, humans have used one simple method to solve problems. Whether it's planting crops, building skyscrapers, developing photographs, or designing the first microchip, all creators follow the same steps to engineer progress. But this powerful method, the "engineering method", is an all but hidden process that few of us have heard of-let alone understand-but that influences every aspect of our lives. Now, for the first time, Bill Hammack reveals the invisible method behind every invention and takes us on a whirlwind tour of how humans built the world we know today. From the grand stone arches of medieval cathedrals to the mundane modern soda can, Hammack explains the golden rule of thumb that underlies every new building technique, every technological advancement, and every creative solution that leads us one step closer to a better, more functional world. Spanning centuries and cultures, Hammack offers a fascinating perspective on how humans engineer solutions in a world full of problems.