In 2000 the world's leaders agreed on an ambitious plan to drastically reduce global poverty by 2015. Called the Millennium Development Goals, the targets spurred an unprecedented aid effort that brought lifesaving medicines and vaccines to millions of people and helped slash the share of people in the developing world who live in extreme poverty from 47 percent in 1990 to 14 percent today.

Now nations are hammering out an even broader set of goals for 2030. But many of the people who work to end poverty fear the list has gotten out of control. By prioritizing so many issues, do you risk prioritizing none?

"You do risk a real dilution of focus and energy and resources," says Mark Suzman, who oversees global policy advocacy for the Bill and Melinda Gates Foundation. "The worst case scenario is we might actually see some regression in some key areas where we have had so much momentum."

To understand why the new set of targets — they'll be called the Sustainable Development Goals — have become so voluminous, you need to go back to the astonishing, sleeper success story of those original Millennium Development Goals.

For an agreement that's widely considered revolutionary, the MDGs, as they're known, had a pretty humdrum beginning.

Mark Malloch-Brown was part of a small group of top United Nations officials who largely wrote the Millennium Development Goals. He sums up the process as "brilliantly simple."

"It was myself and some chums in a room kind of thing."

The process was so casual, they almost forgot something:

"Happily having sent these things to press, I ran into a smiling German colleague in the corridor ... who was the head of the environment program. I remember my blood falling to my ankles as I said, 'Oh goodness me, we've forgotten the environment goal!' "

They stopped the presses and added the goal "Ensure Environmental Sustainability," bringing the total to eight.

A big reason this could all be so low-key was that at the time, people didn't expect much to come of the goals. "It's not as if 2000 was the first time that the U.N. has come out and set lofty global goals," says the Gates foundation's Suzman. (The foundation is a supporter of NPR.)

But Suzman, who once worked with Malloch-Brown at the U.N., says the very simplicity of the Millennium Development Goals ended up making them uniquely powerful. International aid to poor countries had gotten kind of scattershot during the 1990s. Reducing the global agenda to eight narrowly defined priorities helped channel everyone's energies — and money.

"What the goals did by prioritizing and focusing was actually put together major international donors, civil society partners on the ground, national governments focusing on the same sets of issues," says Suzman. "And that allowed for a focusing of both policy change and resources and attention."

Countries and donors could track how they were measuring up against the targets, and this often spurred them to try harder. The upshot: More than 6 million lives have been saved thanks to malaria prevention and treatments; 12 million people in poor countries now have access to HIV/AIDS drugs; and thanks to expanded measles vaccination of children, more than 15 million deaths were averted.

The world hasn't met every single Millennium Development Goal. And a lot of the rise in poor people's incomes was the result of economic growth in China and India.

Still, says Suzman, "the last decade has seen arguably the greatest improvements for the largest number people on the planet in the most countries than has ever happened in human history."

So as people started talking about what should replace these goals when they expire this year, there was one thing everyone agreed on: Something this important should no longer be drafted by a bunch of technocrats in a room at the U.N.

"Oh, it's hugely different," says Thomas Gass, an assistant secretary-general at the U.N. in charge of coordinating the process this time around. "This time it was a two-year process that involved all the member states, that invited interest groups and civil society to come and provide their inputs, their comments." They also polled about 7 million people.

Malloch-Brown, the former U.N. official who helped draft the Millennium Development Goals, says the inclusive approach this go-round is admirable and important. But there's a downside.

"We are victims of the success of the original goals," he says. "They've so much driven decisions about funding by both governments and donors that everybody, whatever their issue, wants to make sure they're included."

The result: The current draft — which is expected to be adopted pretty much as is at the U.N. this fall — lists more than double the number of original goals, and quadruple the number of subtargets. In total the Sustainable Development Goals consist of 17 goals and 169 subtargets.

A lot of the goals expand on unfinished business in areas like reducing child and maternal mortality, fighting disease or boosting incomes. For instance, the original goals called for cutting in half the share of people living in extreme poverty — meaning people who get by on less than $1.25 a day. Now the aim is to get the share down to zero.

But a wealth of new topics is addressed, with targets such as "promote sustainable tourism" and "provide universal access to safe, inclusive and accessible, green and public spaces, in particular for women and children, older persons and persons with disabilities."

"All of them are incredibly important," says Suzman. "There's not a single one of the 169 targets that you would look at and say, 'That's a bad thing.' "

But, he says, "the challenge is, how do you use those to prioritize?" The power of the Millennium Development Goals was that they were "realistic, measurable, and relatively few in number." By expanding the list into such a holistic, broad vision, "you risk not having that energy and direction that came from the Millennium Development Goals and that turned into action on the ground."

The U.N.'s Gass counters that this criticism misses the point of the Sustainable Development Goals. The objective isn't just to update the original goals. It's to usher in a whole new chapter — even a whole new paradigm — for eliminating global poverty.

"The strength of this new agenda is not its focus or its help to set priorities," he says. "The strength of this new agenda is that it can and must become a new social contract between governments and their people."

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