Wies Mauduit attended the Charles Montaigne Fashion Academy in Amsterdam (now the Amsterdam Fashion Institute), where she learned the basic skills of hat designing and millinery from Elizabeth van der Helm as part of the Haute Couture curriculum.

Subsequently she worked in Paris for 24 years. First at the milliners Jean Barthet, where she completed her training. The House Barthet produced hats for the collections of well-known fashion designers such as Chanel, Emmanuel Ungaro, Jean-Louis Scherrer, Claude Montana and Sonia Rykiel.

She then worked at the Comédie Française, the French National Theatre that has its own costume department, where she was responsible for the millinery workshop.