He was a co-founder of the structural engineering and consulting firm Schlaich Bergermann Partner.
He spent 1959 and 1960 at the Case Western Reserve University in Cleveland, United States.
Schlaich was made a partner and was responsible for the Alster-Schwimmhalle in Hamburg, and more importantly, the Olympic Stadium in Munich.
In 1974 he became an academic at Stuttgart University, and in 1980 he founded his own firm, Schlaich Bergermann Partner.
In 1993, with the roof of the Gottlieb-Daimler-Stadion (since 2023 MHPArena) in Stuttgart, he introduced the "speichenrad" principle to structural engineering.