Water and sanitation has not had the same kind of champion that global health, and even education, have had.

What happens when corn and wheat prices rise is that we see real increases in malnutrition and under-nutrition. And when children are malnourished, their brain development actually slows down and is affected. So this is not just a short-term impact.

If we do not act to curb climate change immediately, we will leave our children and grandchildren an unrecognizable planetIt is the poor, those least responsible for climate change and least able to afford adaptation, who would suffer the most.

We have to find climate-friendly ways of encouraging economic growth. The good news is we think they exist.

We will never end poverty if we don't tackle climate change.

There will be water and food fights everywhere.

Ending poverty and ensuring sustainability are the defining challenges of our time. Energy is central to both of them.