  Herbert Gr{\"o}tzsch is the main founder of the theory of quasicon-formal
mappings. We review five of his papers, written between 1928 and 1932, that
show the progress of his work from conformal to quasiconformal geometry. This
will give an idea of his motivation for introducing quasicon-formal mappings,
of the problems he addressed and on the results he obtained concerning these
mappings. The final version of this paper will appear in Vol. VII of the
Handbook of Teichm{\"u}ller theory.
