Yachtswoman Ellen MacArthur has set herself a new long-distance challenge - creating an educational foundation to promote sustainability.
Now retired from racing yachts, she has committed herself to changing attitudes towards the planet's finite natural resources.
She wants to persuade young people and businesses to re-think how they use and design products.
"The foundation will be a catalyst for change," she says.
Speaking in London ahead of the launch of the project, Dame Ellen says that this vision of a more sustainable economy has replaced her consuming passion for sailing.
"Five years ago I would never have dreamt I'd be doing this," she says. "But it's become the most exciting thing I've ever done - and I never thought I could say that about anything other than sailing."
The inspiration for this sustainable way of living came from her experience of long-distance voyages, she says.
"When I was at sea I managed whatever I had incredibly carefully, so I never left a computer screen on, never left a light on, I was careful with food, because you know that is all you have."
"What you have on board is finite. If you drop the only screwdriver over the side, it's gone forever. There is no more. You have to live in a very different way."
It started to make her think of the world as being like a boat stowed with finite supplies - except that unlike the frugal long-distance sailor, as a society we were tearing through what was left of the oil, gas and coal.
When she began examining the alarming rate at which resources were being used - she found herself wanting to do something about it.
"I'd come across something. From the moment I discovered it, it was as if I'd picked up a stone that I couldn't put down again."
The foundation will promote ideas for businesses, schools and universities which will encourage people to re-think how the earth's resources are being used.
This isn't a moral message, she says, but a practical one - a form of enlightened self-interest.
The increasing expense of raw materials is going to drive the development of more efficient ways of working, she says - and she wants her foundation to encourage young people to develop such changes.
Products and services will have to be designed to minimize waste - and she says jobs will be created to serve this new economy.
She says the point is not to urge people to consume less, but to make sure that products are made from materials that can be re-used.
Anything from carpets to washing machines to cars should be re-designed in a way that means that nothing ends up taking the one-way trip to the landfill.
"It's about designing things so that the materials used for a shirt can be re-used for another shirt or turned into a pair of trousers. It's not about using less and less. It's about finding a cycle that works."
But a word she doesn't use is "green". And she admits to having difficulty with the terminology of environmentalism, aware that the language of the eco-warriors can have a negative effect.
"What does 'green' mean? It's not about 'green' or 'the environment'. You could argue it's about how we maintain a good quality of life. It's about how we're going to prosper in the future, when we're so dependent on something that won't be around forever."
Even the word "sustainability" is less than compelling, she suggests - saying that you wouldn't want to describe a relationship with someone as "sustainable".
But there is no doubting the seriousness of her intention - applying the dedication of the long-distance yachtswoman to the long haul of promoting her arguments.
There are links being set up with universities, partnerships with businesses and talks with educational organizations.
The foundation also provides another horizon for someone who achieved their lifetime's ambition at an early age.
After setting a world record for a single-handed circumnavigation of the globe at the age of 24 - and becoming the country's youngest dame - she was left with the "What now?" moment.
"Round the world had been my goal - and the moment I'd got there, it wasn't there any more, I'd done it."
Dame Ellen is now recycling her own energies into launching the sustainability foundation - and says she is optimistic about a positive result.
"This is an inspirational message, an aspiration - but getting there will be the most herculean challenge we've ever faced."
- Scotsman : Ellen MacArthur interview : voyage of self discovery