DW: Helen Clark, do we need a new definition of development?

Helen Clark: We need a new paradigm and that paradigm is sustainable development. In that paradigm, the development people and the environment people have to talk to each other because if we develop in a way that destroys our ecosystems, we will undermine our potential for human development. With sustainable development, we have to be looking for ways to lift people's quality of life while we protect the ecosystems we depend on. So we definitely need new thinking about how to integrate these different strains.

By sustainability most people understand an ecologically less harmful practice than what we see today. What would be your definition of sustainable development?

There are three pillars to sustainable development. There is the economic, there is the social and there is the environmental. And by not trying to see these different things as trade-offs against each other, we should look at how we can advance all the goals at the same time. When you look at a sector like energy - if we can transform the world's energy systems it will be better for the environment, it can create cleaner, greener jobs that can secure people's living standards and secure society. In the work we do in the developing world, we very much advocate these triple win approaches.

DW: Do industrialized countries need to find a new definition of development for themselves as well?

At the moment, those of us on Earth are like passengers on a runaway train, living as though we had three to four planets to exploit. We don't have three to four planets to exploit; we have one planet with a growing population, with depleting resources. And yes, we have to change - that was the big message of Rio +20. Now a particular responsibility for leading that change does lie with developed countries, like my own country [New Zealand] or like Germany, because the heavy carbon stock that is in the atmosphere is the one that largely we created. We should be working extremely hard to reduce our own emissions, but we also need the emerging and developing countries to go on a more sustainable path. The big ones can fund themselves - China will fund its own development, India will fund its own development, so will Brazil. But those of us working in development at the UN or in German development cooperation, really need to focus resources on the poor countries that need to build the capacity to find a different pathway.

The latest Worldwatch Institute Report "Is Sustainability Still Possible?" speaks of "sustainababble" - talk instead of action. Do you see areas where action is actually taking place or are we still stuck at the talk level?

Rio+ 20 produced a big outcome document and it said all the right things about the problem. But the international community has not been very good on agreeing on the solutions. We see that with the climate negotiations where the negotiators go back time and time again. We haven't got the breakthrough yet. We need that breakthrough; we need it in 2015 - that is the date that has been set - so I think there needs to be a lot of focus now. Because when we are talking climate change, it is almost a proxy for saying our biodiversity is diminishing, we have problems with our oceans, our land quality is diminishing, our water quality is diminishing and our forest cover is dying. If we tackle climate, we actually tackle a very wide range of these huge issues on the environment.

Where do you see the role of the United Nations Development Program (UNDP) in promoting sustainable development?

The UNDP has been a leader on human development starting with the incredibly important thinking of Amartya Sen and collaborators on the human development paradigm a quarter of a century ago. Sustainable development is not as simple as just saying I will pay for children to go to school or I will pay for people to have their baby in the hospital. Actually there may be all sorts of factors why children aren't in school or women cannot access the health services or the death rate may be high for mothers because there are a lot of very young mothers.

We looked at this recently with the example of Ghana, which declared its maternal mortality rate a national emergency. And the higher rate of death is among 12-15 year-old girls - girls too young to be having babies. They should be having a childhood and adolescence and making some choice about their lives.

At the UNDP we embrace a rights-based approach to development. We believe in Millennium Development Goals with equity. We are not just interested in figures and averages, we want to know if progress is reaching every last person.

Helen Clark is the first woman to lead the United Nations Development Program, UNDP. She took over the reins in 2009. From 1999 to 2008 the Labour Party leader was prime minister of New Zealand - also the first woman to hold that position in the country.