Over the past forty years, Mark Ellison has worked on some of the most beautiful homes you've never seen, specializing in rarefied and challenging projects with the most demanding of clients. He built a staircase a famed architect called a masterpiece. He worked on the iconic Sky House, which Interior Design named the best apartment of the decade. He's even worked on the homes of David Bowie, Robin Williams, and others whose names he cannot reveal. He is regarded by many as the best carpenter in New York. But before he was any of that, Ellison was just 'a serial dropout' who spent his young adult years taking work where he found it and sleeping on couches. In How to Build Impossible Things, Ellison tells the story of his unconventional education in the world of architecture and design, and how he learned the satisfaction and joy that comes from doing something well for a long time. He takes us on a tour through the lofts, penthouses, and townhouses of New York's elite which he has transformed over the years - before they're camera-ready - and offers a window into what he's learned about living meaningfully along the way. Scrapped blueprints and last-minute demands characterise life in the high-stakes world of luxury construction. From staircases that would be deadly if built as designed to algae-eating snails boiled to escargot in a penthouse pond, Ellison exposes the messy wiring behind the pristine walls - and the mindset that any of us can develop to build our own impossible things.