Best known for his Tom Turbo stories and his The Knickerbocker Gang series, this popular Austrian children's author published more than five hundred books and had his work translated into nearly forty languages. Also a television personality, he hosted or appeared on more than forty children's shows.
Early in his career, he earned the Grand Austrian Youth Prize for his screenplays for a popular television puppet show. He later worked as the director of a children's TV series called Am dam des.
In 1996, he became an Austrian UNICEF Goodwill Ambassador.
A native of Vienna, Austria, he later lived in both his home city and in London, England.
He and fellow Austrian writer Eva Ibbotson both became known for their works of children's literature.