In 1948 he joined Standard Elektrik Lorenz (SEL, part of the ITT group) in Stuttgart, as a computer design engineer and later as a director of research and development, where he filed more than 70 patents.

[citation needed] Steinbuch completed the first European fully transistorized computer, the ER 56 marketed by SEL.

[1] In 1958 he became professor and director of the Institute of Technology for information processing (ITIV) of the University of Karlsruhe, where he retired in 1980.

In 1967 he began publishing books, in which he tried to influence German education policy.

predicted what he regarded as the coming education disaster of the emerging civic lobby society.