The German pavilion at the 1967 World Exhibition in Montreal, the Congress Centre in Mecca in 1974, the roof of the Olympic Stadium in Munich in 1972, the Multihalle in Mannheim in 1975 and the Berlin Ökohaus in 1990. All these and many other projects and buildings are closely linked with the name of Frei Otto and his theoretical and experimental research at the Institute for Lightweight Structures.