He returned to Austria in 1971 and worked as an independent commercial artist and draughtsman. He developed his photo-realistic style working on advertising, illustrations, and even designing maps for the Salzburg tourist board. In 1985, after a cancer operation, he abandoned his commercial career to become a freelance caricaturist and satirical illustrator. His first satirical works appeared in the upper-Austrian magazines "Watzmann", "ORF-Ventil" and "Oberösterreichische Nachrichten". He soon began to appear regularly in the Austrian weekly “Profil" to which he still contributes. His work then began to appear in newspapers and magazines in other German speaking countries. Since 1991 his work has appeared regularly in Germany’s "Stern" magazine as “Haderers Wochenschau” ("Haderers weekly news"). From 1997 to 2000, and from 2008 he published his own monthly satirical comics magazine called Moff". He has produced designs for several satirical puppet shows.