LONDON - Princess Diana, first wife of the heir to the British throne, died aged 36 in Paris on Aug 31, 1997, after the limousine carrying her and lover Dodi al-Fayed crashed in a tunnel as it tried to escape paparazzi who were chasing them on motorbikes.
As the 20-year mark grows closer, new documentaries and books are revealing more about her once-hidden personal life with Prince Charles.
A look at some of them:
Diana, Our Mother: Her Life and Legacy
In this ITV documentary aired on July 24, Prince William and Prince Harry revealed that they spoke to Princess Diana on the day she died and that the "short" conversation now weighs "heavily" on their mind.
"It was her speaking from Paris, I can't really necessarily remember what I said, but all I do remember is probably regretting for the rest of my life how short the phone call was," Prince Harry told ITV for a documentary to commemorate their mother.
Prince William was just 15 and his brother, Harry, 12, when their mother died.
They also recall the pain of their parents' divorce, and how they dealt with the news of her death and its aftermath.
While the film addresses such aspect of Diana's life as her charity work involving HIV and landmines, it shies away from more controversial issues, such as extra-marital affairs.
According to the makers, however, the British royals were very open, and did not put any subject off limits. Rather, they wanted to cover new ground and make a different type of film.
Diana: In Her Own Words
To be aired on Aug 6 by Channel 4, this documentary will show footage of Princess Diana speaking about her marriage during privately recorded sessions with an adviser on public speaking.
The footage includes Diana speaking about her sex life with Charles.
"It was just so odd. I don't know there was no requirement for it from his case," Diana says. "Sort of once every three weeks." "And then I followed a pattern, he used to see his lady once every three weeks before we got married," she said.
Diana also relates how she approached Queen Elizabeth to discuss the failing marriage. "She said, 'I don't know what you should do, Charles is hopeless'. And that was it," Diana said.
She also said Charles' father, Prince Philip, had given him permission to have an affair if the marriage did not work.
The footage of Diana was filmed at Kensington Palace in 1992 and 1993 by speech coach Peter Settelen.
After a lengthy court battle, the tapes were handed to Settelen. Segments of the tapes were aired in the United States by channel NBC.
In 2007, British broadcaster the BBC also tried to use the tapes for a documentary, but the film was scrapped.
Diana and the Paparazzi, Diana: The Day We Said Goodbye
The two specials are scheduled to air on Smithsonian Channel on Aug 27 one after the other. Both look at the public and media fascination with Diana - before and after her death.
While the first examines how she handled the constant media attention and the role of the paparazzi in her death, the second looks closely on the day of her funeral, when millions turned out in the streets of London to bid her goodbye.
Remembering Diana: A Life in Photographs
Released on Aug 1 by National Geographic, the book features more than 100 images of Diana.
It has a forward by Tina Brown, her friend, biographer and former editor of Vanity Fair and The New Yorker.
"Twenty years after her death we miss her more than ever," especially her humanity and the "bond of compassion she forged with her admirers," Brown writes.
Diana: I'm Going to Be Me
This book of quotes by Diana was released on July 1, the princess' 56th birthday.
Compiled by Phil Dampier, it includes memorable quotes such as: "The trouble with being a Princess is that it is so hard to have a pee."
SOURCES: AFP, FORBES, USA TODAY, ENTERTAINMENT WEEKLY