This book elegantly traces the genesis of David Chipperfield’s extension for the Kunsthaus Zürich. David Chipperfield’s new building for the Kunsthaus Zürich now stands in all its splendor on Zurich’s Heimplatz, opposite the old museum building of 1910 designed by Karl Moser. Its opening to the public in October 2021 will make the Kunsthaus Zürich Switzerland’s largest art museum. Following two previous volumes on Kunsthaus Zürich’s architectural history and the design used to turn it into an art museum for the twenty-first century, this book documents the genesis of Chipperfield’s extension from proposal through political debates about the entire project to the completed structure. It features a foreword by Chipperfield and an essay by Christoph Felger, executive architect for the project at David Chipperfield Architects Berlin, that discusses the design concept, the promise made with it, and its fulfillment. A conversation between Felger, director of the City of Zurich’s Building Surveyor’s Office Wiebke Rösler, Kunsthaus Zürich’s director Christoph Becker, and architecture critic Sabine von Fischer, as well as numerous illustrations and plans round out this new volume.