Gregor Eichinger argues that since the beginning of modernity the concept of surface has been neglected by architecture. A tendency for simplification, for a reduction to the abstract space and the material are the reason that today the topic is given such short shrift. Based on his research as a professor at the ETH Zürich, Eichinger calls for a serious discussion about the architectural user interface. In an intensive conversation, he and architect Eberhard Tröger discuss what alchemy has to do with architecture, why a good bar has to be a sketch, how one reads ornament, why we no longer look up at the ceiling, why cleanliness gets in the way of everything, how architecture is created from the inside, and much, much more. The text of this conversation is interwoven with a variety of related quotations and complemented by a series of images that deal with the relationship between architectural surfaces and people.