Hadank studied graphic design under Emil Doepler at the Vereinigte Staatsschulen für freie und angewandte Kunst Berlin (United State School for the Fine and Applied Arts) from 1905 to 1910.
He did not join the modernist movement, but developed a distinct style of his own which often implied the use of heraldic symbols.
In 1919, Hadank was among the founding members of Germany's first professional organization for graphic designers, the BDG.
Appointed professor by Bruno Paul in the same year, Hadank was in charge of the advertising design department at the Vereinigte Staatsschulen für freie und angewandte Kunst Berlin until 1945.
Hadank was not a great innovator, and contemporary graphic design histories barely acknowledge him, he was an influential teacher.