World leaders will meet at a special session of the UN General Assembly on September 25 to discuss how to accelerate progress on the Millennium Development Goals (MDGs), and also to agree on a timetable for a new set of Sustainable Development Goals (SDGs). The MDGs, adopted in 2000, will conclude in 2015, to be followed by the SDGs, most likely for the 2015-2030 period.

The MDGs focus on ending extreme poverty, hunger and preventable disease. They have been the most important global development goals in the UN’s history. The SDGs will continue the fight against extreme poverty, but also add the challenges of ensuring more equitable economic growth and environmental sustainability, especially the key goal of curbing the dangers of human-induced climate change. Setting international development goals has made a huge difference in people’s lives, particularly in the poorest places on the planet.

As Special Adviser to the UN Secretary-General on the MDGs since 2001 (to Kofi Annan until 2006 and to Ban Ki-moon since 2007), I have seen how seriously many governments take the targets, using them to set priorities, catalyse stakeholders, increase public awareness and motivation, and hold ministries accountable. While the MDGs are not the only factor underpinning the improvements since 2000, they have played a huge role.

Of course, much remains to be done to maximise progress on achieving the targets set by the MDGs, especially in poor countries. Most important, significant gains in health could be attained with adequate financial resources. Donor countries should provide ample replenishment funding later this year to the “Global Fund to Fight AIDS, TB and Malaria”, which would ensure this vital agency’s continued success.

When UN member states turn to the next set of global development goals, they should learn from the MDGs. First, keeping the list of SDGs relatively short - no more than 10 - will make them easy to remember, which will help in mobilising the public.

Second, all governments, rich and poor, should be accountable for meeting the SDGs as implementers. The MDGs applied mainly to poor countries as implementers and to rich countries as donors. The SDGs should apply to all countries as implementers (and also to rich countries as donors). Indeed, when it comes to problems like climate change, which will be at the core of the new SDGs, rich countries have more work ahead of them than poor countries do.

Third, the SDGs should build on the MDGs. The MDGs helped to cut global extreme poverty by more than half. The SDGs should take on the challenge of ending extreme poverty for good. The World Bank, to its credit, has already adopted the goal of ending extreme poverty by 2030; UN member states should do the same.

Finally, the SDGs should mobilise expert groups around the key challenges of sustainable development. When the MDGs first appeared, the relevant specialists began to organise themselves to give advice on achieving them. The “UN Millennium Project” synthesised the counsel of roughly 250 global experts on crucial development issues. The same process of expert advice and problem solving is urgently needed on issues such as low-carbon energy, sustainable agriculture, resilient cities and universal health coverage, all of which are likely to feature in the SDGs.

Fifty years ago, US President John F. Kennedy declared: “By defining our goal more clearly, by making it seem more manageable and less remote, we can help all people to see it, to draw hope from it and to move irresistibly towards it.” The MDGs have helped to play that role in the fight against poverty. The SDGs can do the same for the complex challenge of achieving sustainable development.

The writer is professor of economics and director of the Earth Institute at Columbia University. This article has been reproduced from Project Syndicate.