The continued use of existing buildings is becoming increasingly important in view of the growing pressure to renovate. Converting and rebuilding makes ecological sense and continues the architectural and spatial history of our cities. Terms such as conversion culture, sustainable transformation and adaptive re-use are dominating the architectural discourse. But instead of just reacting to what already exists, the question arises as to how we can think about the ability to rebuild and reuse from the outset and establish this as a planning basis for new buildings. The new building of today is the existing building of tomorrow. What characterizes a convertible building? Which existing buildings can be adapted well, and why? How can the future transformation be taken into account at the pl ...