As a boy growing up in Romans, France, Charles François Louis Jourdan III saw his father, Roland, only on Sundays. The elder Jourdan was too busy managing the international shoe company founded in 1921 by his father, the original Charles Jourdan. But since 1976, when young Charles launched his own interior design house, called Jean-Charles, he has been talking nearly every day to Papa Roland at company headquarters. That's because 26-year-old Charles is now responsible for the design or refurbishing of Jourdan stores all over the world. (Of the 87 stores, he has done 60 so far.) Jourdan does not rely solely on nepotism for jobs. He has won over some of the competition, too, designing boutique interiors for Ungaro, Dior and Yves Saint Laurent.

As for the Jourdan father-son business encounters, which have not always been serene, Charles admits, "It was hard for my father to be my client. I call him Monsieur Jourdan and always shake his hand. I never call him Papa. Working with him is always a battle. My father says, 'Jourdan doesn't sell decor. It sells shoes.' In the end I have to admit my father is right." Charles, who logs up to 70,000 air miles a year, is amused that designer Ungaro sends him first-class, but Papa Roland insists he travel tourist.

No matter. Charles is particularly proud of his latest Jourdan store. It's on Wilshire Boulevard in Beverly Hills and features bleached pine, raw bricks, a mirrored ceiling and beige and navy leather banquettes. Explains Charles, "We're moving back to natural wood and stone. I'm tired of seeing busy, overdecorated interiors. I prefer simplicity and space with a lot of light." Since its opening last July, Hollywood types like Suzanne Somers, Angie Dickinson, Nancy Sinatra and Cicely Tyson have come by to gawk (and buy) at the largest and most glamorous property in the Jourdan chain. Beverly Sassoon alone spent $2,400 on shoes and accessories the day after the opening.

A fanatic about details, Charles designed everything in the store—except the shoes—from the shopping bags to the lacquer-red shoeboxes. He made sure the plain beige carpet had a low pile—the better to see the shoes. Because he also chooses the background music for all the Jourdan boutiques, he knows that disco sells more shoes than classical or pop. "Whenever a job is finished, I want to do it over and over again to make it more perfect," admits Charles, who tries to sound modest about his talents. "I know I'm not Picasso."

The most artistic of Roland Jourdan's five boys and girls (he is the third eldest), Charles as a schoolboy drew birthday cards on request for his siblings and doodled tirelessly in his textbooks. "I was very bad at school," he remembers. "I changed many times. I always managed to leave just before I got kicked out." In Geneva when he was 16 he fell in love with his future wife, Ayse Cobani, a Turkish girl educated in England. Both of them were studying at the International School. About their courtship Ayse recalls, "He was typically French. And I was typically English. I wore pleated skirts and was very prim and proper. It didn't seem it could ever work." Charles remembers with a chuckle, "I spoke to her in bad English. She answered in bad French. She wasn't my first girlfriend. But she was the one who stayed the longest." Two years later, without telling his parents, Charles transferred to Lausanne's Arts Ecole Graphisme to study design. "I honestly thought I would not succeed in science and economics," he says. "I turned to something that pleased me."

Nowadays the young Jourdans and their two children, Stephanie, 3, and Thomas, 1, live in an apartment in the historic Marais district of Paris. As for their flat, done in modern style with Japanese undertones, it is still unfinished after four years. Ayse, 27, says, "Decorators always have the worst apartments. We're like the cobbler's children. We come after everyone else." Nonetheless, she reports that Charles "is the kind of parent who wakes up three times in the night to check on the children." The Jourdans, who own a children's clothing store, Bébé Charles, on the Right Bank, lead a hectic social life. "I receive many invitations on my name alone," Charles says. "But we like it. Going out is good for business."

Although the Jourdan family connection obviously helps—last year Jean-Charles grossed $1 million—Charles does not always tell clients his real name. "When I first meet a client I call myself Monsieur Jean-Charles. But there are also clients who are flattered to know who I am." Charles pauses as if to add up the pluses and minuses, and then shrugs. "As a Jourdan, I'm always judged in advance. I don't have the right to make mistakes."