Another formative, fashion-related experience that Princess Maria-Olympia spoke with British Vogue about was her Christian Dior Couture internship. "I found it incredible," the princess said, "seeing the step-by-step process behind it all, and how hard everyone works." 

Maria-Olympia had not yet gone to college at the time of the internship and was younger than the other interns. "I was just putting the shoes on the models," she said of her responsibilities. "Backstage at the show, I had to make sure that look 37's train looked perfect." Maria-Olympia later studied fashion (along with business and marketing) at New York University.

In a Teen Vogue interview from 2014, just a year after she had interned with Christian Dior but prior to going to college, Maria-Olympia described the internship as an enjoyable, educational experience. She also revealed that she and her mother Princess Marie-Chantal Miller have the same shoe size, so they share shoes and other clothing items. Sharing clothes with the women in her family is something Maria-Olympia has done since childhood.