From a shy kindergarten teacher in flat shoes, giant collars and dowdy skirts to a sleek princess who knew how to work the cameras and steal the spotlight, Diana became an enduring fashion icon whose style still resonates today.
Whether she was dashing into a gym in bike pants or stepping out of a limousine in an ethereal gown, the cameras were always at the ready, the press coverage ensuring her fashion choices were well documented.
But given the height of her fame fell in those treacherous fashion decades of the 80s and 90s, some fashion crimes were bound to be committed.
On the 20th anniversary of her untimely death, we take a look back at some of the princess' best and worst fashion moments.
Diana twisted and twirled in a midnight-blue Victor Edelstein gown on the White House dance floor with movie star John Travolta. The pair danced the night away at the 1985 State dinner.
• The Elvis Dress, 1989
An iconic Diana look, this was the Catherine Walker pearl and sequin dress that the princess herself dubbed "The Elvis Dress".
• Diana at The Serpentine Gallery, 1994
A strategic choice, Diana wore this stunning number the same night Charles was off celebrating Camilla's 50th birthday. The next day it was clear Diana had won in the attention stakes gaining far more press coverage in her revealing Christina Stambolian dress than Camilla had over her birthday bash.
• Cannes Film Festival, 1987
Another Catherine Walker dress, Diana was the epitome of elegance in this strapless pale blue chiffon number worn on the Cannes Film Festival red carpet.
Diana wowed in this figure-hugging Versace dress with matching clutch worn on the red carpet of a Cardiac Research dinner event.
• Arriving at the ballet, 1997
The princess literally sparkled in an ice blue Jacques Azagury mini dress at a gala performance of Swan Lake in London.
• Red Cross dinner in Washington, 1997
Choosing the perfect shade for a Red Cross fundraising dinner in Washington, Diana continued to utilise fashion to cement her status as a modern-day princess.
• Prince William's confirmation, 1997
Equal parts chic and demure, Diana chose this blue two-piece Chanel suit and hat for her son's religious ceremony.
• Royal Ascot, 1987
Navy and white stripes are always a sophisticated look and, of course, Diana knew this. Here she wears a Roland Klein two-piece with pleated skirt and blazer. Ensuring the look remained regal she teamed the outfit with a Chanel blouse, a white wide-brimmed hat and white purse. The pearl choker she often wore was a birthday present for her sweet sixteenth.
• The naming of the Royal Princess cruise liner, 1984
To take a tour of the P&O Cruise Liner named after her in Southampton, UK, Diana wore a scarlet knee-length dress with gold buttons and black accessories including a frilled scarf, gloves and a shiny clutch. She topped off the look with a matching beret.
DIANA'S WORST OUTFITS
• Charles and Diana on their honeymoon, 1981
Honeymooning in Scotland, Prince Charles wore a traditional tweed kilt. It appears Diana thought it essential to wear a tweed-inspired woollen two piece to match. But her "suit", designed by Bill Pashley, presents itself as frumpy and reminiscent of an 80s-era school uniform.
• Diana and Charles meet the Pope, 1985
No, she's not going to a funeral. Diana wore this black lace dress and veil, designed by Catherine Walker, to meet Pope John Paul II at the Vatican in Rome.
• Diana in Japan, 1986
Diana was on an official trip to Japan and made the odd call to dress as the Japanese flag.
• Nigerian state banquet, 1989
She may be wearing the Spencer family tiara but teamed with all that lilac satin, Diana does royalty a disservice on this occasion.
Dressing for the event, Diana wore this full plaid dress at the Braemar Games in Scotland. Featuring a big hat, big buttons and a big collar, it's clear exaggerated accessories were thought the order of the day.
• Charles and Di on a farm, 1981
When the royal couple were engaged, the princess wore this, somewhat striking, Inca sweater and gummy combo. Casual and comfy, we're sure, but not one of her best looks.
• The Royal Ballet in Berlin, 1987
Another of Catherine Walker's creations, this time an off-the-shoulder pink and white satin gown paired with pearls. The Disney-esque skirt attached to an ill-fitting bodice marks a confused point in Diana's style story.
• Prince William's birth, 1982
When Diana presented her newborn Prince and Future King to the world, she wore this shapeless green spotty number featuring a white pussy-bow. It was 1982 and probably right on trend as far as maternity style was concerned. In hindsight, it looks like something wee William's grandmother would wear to bed.
• Windsor polo match, 1986
Not something you would imagine a royal wearing to a Polo match in Windsor, this is another red and white 80s nightmare: A sweater over a spotty skirt with spotty socks to match.
• Diana and Charles in Italy, 1985
Princess Diana wore this blue tartan suit, made by Emanuel, the same designer as her wedding dress, during a walkabout in Italy with her husband Prince Charles. The giant matching "pirate" hat should have been left at home.