Wearing a cap, cropped leggings and gold heeled sandals, Agnès b. moved gracefully, agelessly. That day, she had slipped on a white snap cardigan over her striped T-shirt. She had another black one with her, "in case it gets cold. This cardigan is like a cup of hot chocolate," she said. It's a simple, comforting, timeless garment − and still a best-seller, 46 years after its creation.

We met the designer in her Paris office at 17 Rue Dieu, where she has been based since 1994. It has immaculate white walls and a few vanilla-strawberry hydrangeas picked from her garden in Louveciennes, near Paris. An open sketchbook, books and cut-out press clippings decorate the space. On a glass pane, there's a drawing from her friend Jean-Charles de Castelbajac. On the walls, held up with black tape, are posters of films by Jean-Luc Godard and Harmony Korine and of the first painting by Jean-Michel Basquiat she bought.

"Sparkling water or coffee?" she asked. Barely settled on her sofa, cigarette lit, Agnès b., 83, joyfully went back through her memories: meeting Picasso at age 14 on the stairs of Château Grimaldi in Antibes; her recent appearance at the latest Cannes Film Festival to greet her friend Robert De Niro; and stories featuring Jean Seberg and Romain Gary, Yoko Ono and Sean Lennon, Gilbert & George.

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