The United Nations Rio+20 Conference last year called for urgent action to put the world on a more equitable and sustainable development path. Countries agreed that systems and behaviors that worsen poverty and inequalities, exclude women and marginalize others, are pushing our planet to its limits and must change.

Sustainable energy yields benefits beyond the environment. It enables children to study at night, allows health clinics to store needed vaccines, and frees women from backbreaking chores and life-threatening smoke from wood-burning stoves. It creates a platform for better and more productive lives.

We are all called on to pursue integrated approaches to sustainable development, which see economic and social progress as entirely compatible with safeguarding ecosystems. Making the transition to green and inclusive economies and societies must be the goal.

Germany, for example, developed with a heavy carbon footprint but now leads the way in making the transition to sustainability. The renewable share of Germany’s energy mix doubled from 2006-2012. This suggests to me that with bold leadership and farsighted policies, countries can make the transitions to become more sustainable.

Indeed, we have no choice if we are to avoid an irreversible rise in global temperature and its dire projected consequences. These would see citizens in developed countries funding ever more elaborate flood defense systems, compensating farmers for lost crops, and adjusting thermostats to cope with heat waves.

But shifting weather patterns and more extreme climate events in sub-Saharan Africa also mean that as more crops fail, more people go hungry, and more girls spend less time in school and more time collecting water. Visiting the Sahel last year, I saw firsthand the human suffering repeated severe drought brings. It sends development into reverse.

Poor people and poor countries are disproportionately vulnerable to global warming, although they have contributed little to the problem. That is unjust.

The developed world bears a unique historical responsibility to tackle climate change. It must reduce its own greenhouse gas emissions and support poor countries in strengthening their resilience to a more erratic climate and pursue cleaner, low-emissions development.

Many developing countries are taking bold initiatives. Ethiopia, with its far-sighted Climate-Resilient, Green Economy Strategy, has set out to invest US $150 billion over the next two decades to become a carbon neutral middle-income country by 2025. At climate change negotiations, we see least developed countries making ambitious proposals for reductions in their greenhouse gas emissions.

UNDP plays a catalytic role connecting governments, international financial institutions, private investors, and others in supporting countries as they sequence reforms, strengthen legal and regulatory capacities, and attract and use financing.

In development, I often say, we are in the hope business. We see the needs. We see the barriers. But we also see paths to move forward. We believe that just as humankind has brought us where we are today, we can — with vision, leadership, and ingenuity — make development work for the planet and its peoples.