With Diana's death, many causes - some unfashionable or ignored - lost a high-profile and important patron.
Diana's humanitarian work was widely recognised
After her divorce, the princess resigned as head of most of her charities. But she remained as patron of Centrepoint, Leprosy Mission and the National Aids Trust, as well as taking an interest in the campaign against landmines.
She also remained as patron of the English National Ballet, and as President of the Hospital for Sick Children, Great Ormond Street and of the Royal Marsden Hospital.
So how did Diana help some of those charities she loved during her lifetime - and have they prospered after her death?
Diana's role was crucial to landmine causes. It was her highly-publicised trips to Angola and Bosnia that got the media - and the public - interested.
Above all, she highlighted the use of a weapon that was not only deadly but, because it was left behind as part of the litter of war, killed and maimed innocent civilians, particularly children.
Diana's high-profile work against landmines prompted questions from politicians
Keith Kelly, director of the No More Landmines Trust, says: "Where it became part of the public consciousness was when Diana went to Angola and walked through the minefield. It was a successful use of her celebrity."
Those pictures, and those of a subsequent trip to Bosnia, were shown worldwide.
And the fruits of her campaign could be seen immediately after her death. The Mine Ban Treaty was signed in December 1997 by 122 nations.
As Mr Kelly points out, the treaty is not perfect - and certain governments have not signed up. But, even governments who have not signed it are behaving as if they did.
Above all, the treaty stigmatised landmines. The United States, for instance - which did not sign the treaty - has become one of the big funders of action against landmines.
And the work to clear mined areas has continued apace. Since 1999, 2,155,000,000 sq m of land have been de-mined, landmine charities say. This would clear a strip of mine-affected land 10m wide five-and-a-half times around the world.
As the charity points out: it is working to put itself out of business. Landmines are a solvable problem, Mr Kelly says.
"There are thousands of people around the world who have directly benefited from her legacy. There are millions who have benefited indirectly. She has an incredibly positive legacy," he adds.
"In 10 or 15 years time, we hope organisations like us won't need to be there.".
HIV and Aids in the late 1980s were still surrounded by prejudice, ignorance and stigma. Campaigners paid tribute to Diana's work in breaking down the barriers around the disease.
Lisa Power, head of policy at the Terence Higgins Trust, says Diana's example gave people a clear signal HIV was nothing to be ashamed of.
"She was not fazed, not afraid of it," she says.
"There were celebrities [who were raising awareness], but she was not just a celebrity. There was a high level of identification with her. Elizabeth Taylor has done amazing things, but she was out in the USA. Elton John has done amazing things as well but there are people who view it as - well, he's a gay man, he should.
"It was an issue around fellow humanity - she made contact with people."
Rachael Bruce, spokeswoman for the National Aids Trust, agrees. Diana's example of touching patients had a huge impact, she says.
"It really made people realise that those with HIV should not be treated like outcasts. They needed compassion and sympathy.
"She embraced difficult causes and people shunned by others. Diana was keen on challenging the discrimination around it - the stigma that still occurred. She used her high profile position to do that."
Ms Bruce doubts Diana's visits to Aids wards and her personal contact with sufferers were welcomed by royal advisers, but embracing the underdog, she says, was all part of the princess's style.
Touching Aids patients did much to allay fears surrounding the disease
And there have been improvements made in the lives of people with HIV and Aids in the last decade. Treatment has improved for sufferers and people are more informed about the rights of those with HIV. In addition, it is illegal to discriminate in the workplace against anyone with HIV.
But with Diana's death, the Aids movement lost an essential champion, Ms Bruce says.
"Without someone like Diana to support our work and champion the causes, it's increasingly difficult to raise funds.
"There is a silence around HIV - and she did a lot to break the silence. She's been irreplaceable for the charity and the cause. No-one comes close.
"Her death was a blow. Without her support, it's not given the support on the public agenda. Diana did a lot to tackle stigma and discrimination. We are working to continue her legacy - there have been improvements in the 10 years since her death. But there's still this silence and misconceptions."
As with HIV and Aids, Diana's work did much to remove the stigma of leprosy.
Keith Nicholson, director of the Leprosy Mission, says Diana was the charity's first patron - and that they have not had one since her death.
More than 90% of people affected by leprosy live in developing countries
"The work she was doing - it was difficult for anyone to follow in her footsteps," he says.
"The prime thing she did was to raise the profile of the disease - and the fact the stigma is unfounded.
"She sat on the bed of sufferers, touched them, shook hands with them, talked to them. Up to that point, it was not the done thing. She was a champion for those that are marginalised, she showed the world there was nothing to be afraid of."
It has not been easy to attract interest and funding in the past 10 years, although Mr Nicholson says the charity is grateful to be included as one of the charities to benefit from the concert in Diana's memory held in July this year.
And with 300,000 new cases of leprosy each year and education both in the West and in countries where leprosy occurs still needed, there is plenty of work still to do.
Centrepoint, the charity that helps the young homeless, also benefited from the recent concert. Like many other charities, they miss Diana as a figurehead - but also in a private capacity.
"She met our young people and spoke to our staff - and that gave them a sense of value, worth and self-respect," says Edward Hodgkins, director of fundraising. "It's hard to replace."
Mr Hodgkins says: "She saw a valuable group of young people that were marginalised in our society and not only should they not be, but she felt she could do something about it."
The charity feels Diana has left a very solid legacy behind her in that her patronage has passed to her son.
"We are so grateful for the support of Prince William who has been a fantastic support. He's actively involved in what we've done - not just the public element, but he did work experience with us. He's very much recognised as our patron."