Queen Elizabeth II has met all sorts of cool celebrities. But today, on the 15th anniversary of Princess Diana's death, we've taken a closer look at Princess of Wales' most glamorous moments. One of our favorites? A rare time when royal celebrity and fashion celebrity collided.

Kate Moss and Princess Diana, as far as we know, didn't have much of a relationship (unlike another famous royal-model pairing, Sarah Ferguson and Naomi Campbell). But in 1997, the pair crossed paths at Christie's in New York. The royal was on hand to oversee the auction of 79 of her dresses, the sale of which would raise funds for the Royal Marsden Hospital Cancer Fund and the AIDS Crisis Trust. It was a buzzed-about event, drawing the likes of Nan Kempner and Barbara Walters.

Kate Moss also made an appearance, resulting in the fabulous photo opp below.

Take a look and remember Princess Diana for today's Fashion Flashback.

PHOTOS:

princess diana kate moss

princess diana kate moss

Take in Princess Diana's chic fashion:

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  • May 1981

    With Prince Charles at Craigowan Lodge on the Balmoral Estate. (Tim Graham/Getty photo)

  • July 1981

    Posing for pictures on her wedding day. (Lichfield/Getty photo)

  • July 1981

    More wedding pictures! (AP photos)

  • November 1982

    At a banquet at the Guildhall in London. (Anwar Hussein/WireImage photos)

  • July 1985

    At the premiere of "A View to a Kill" in London. (Tom Wargacki/WireImage photos)

  • November 1985

    Wearing a Victor Edelstein gown to a White House State Dinner in Washington, DC. (Pool/Tim Graham Picture Library/Getty photos)

  • July 1990

    Leaving Cirencester Hospital in England after Prince Charles broke his arm during a polo match. (AP photo)

  • January 1993

    At Indian Castle Beach. (Getty photo)

  • June 1994

    At the Serpentine Gallery in London, wearing a dress by Christina Stambolian. (Jayne Fincher/Getty photos)

  • August 1995

    Sitting with Prince Harry during V-J Day celebrations in London. (AP photos)

  • November 1995

    Meeting with Argentinian president Carlos Menem in Buenos Aires. (AP photos)

  • September 1996

    Arriving at a cancer research benefit in Washington, DC. (AP photos)

  • December 1996

    Walking through the Metropolitan Museum of Art in New York to attend the Costume Institute Gala. (AP photos)

  • January 1997

    On a British Red Cross mission to highlight the evil of land mines in Luanda. (Getty photo)

  • March 1997

    Meeting with Nelson Mandela to discuss the threat of AIDS in South Africa. (AP photos)

  • June 1997

    At a gala benefit for victims of landmines at the National Museum of Women in the Arts in Washington, DC. (AP photos)

  • June 1997

    Meeting with Mother Teresa in New York. (AP photos)

  • June 1997

    Leaving Christie's auction house in New York after selling some of her dresses, the proceeds of which went toward AIDS and cancer charities. (AP photos)

  • August 1997

    Arriving at Sarajevo airport on a tour to publicize the international problems of land mines. (AP photos)

  • Princess Diana Letters Up For Auction

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