In 1998, exactly 20 years ago, in the city of Zurich the epoch of replacing existing housing with new buildings began. Since then, in the framework of this strategy, dozens of developments have been demolished and thousands of new apartments have been erected; some districts have changed fundamentally. Time, then, to draw up a first balance: how, in terms of social spaces, urban planning and architecture, has the city changed? Which opportunities were made use of, which ones were missed? Where do the benefits lie and what are the limits of this renewal strategy? We show the extent of change and the concrete effects in numbers, we talk to important protagonists, and present exemplary projects.