25 years ago we were selected by I.M. Pei as associate architect on the design of the Museum of German History in Berlin. Covering the Zeughaus inner courtyard with a glass dome I worked intensely with Professor Schlaich (Schlaich Bergerman). He was the first structural engineer that used the glass itself as structure. Glass can take the compression and the steel cables work the tension. Together they make a super lightweight glass dome that 25 years ago was very revolutionary.