In 1962 Schmidt began work at TU München with students of Robert Sauer, in the beginning in labs and tutorials, later in mentoring and administration.
Friedrich L. Bauer and Klaus Samelson were establishing software engineering at the university and Schmidt joined their group in 1974.
From 1988 until his retirement in 2004, he held a professorship at the Faculty for Computer Science of the Universität der Bundeswehr München.
Working with Thomas Ströhlein, he authored a textbook on relations and graphs, published in German in 1989 and English in 1993.
In 1981 he participated in the International Summer School Marktoberdorf, and edited the lecture notes Theoretical Foundations of Programming Methodology with Manfred Broy.