UNITED NATIONS >> The last time Amina J. Mohammed went home to see her extended family in northern Nigeria, her cousins asked her to skip her usual gifts of clothes and sweets and bring them something that they really needed: body scanners for the gates of the local mosque, to guard against suicide bombers sent by Boko Haram.

Their request summed up for her what has happened to the place she calls home, and how years of dysfunction and destitution had turned the region into a battleground. "Terrorists are not born," is how she put it the other day. "What was it that birthed Boko Haram?"

The answer, in her view, can be found in the problems she has spent the last 3 1/2 years trying to get world leaders to agree to address: corrupt government leaders, crumbling schools, and the effects of climate change. In northern Nigeria and the surrounding Sahel region, that has meant the aggressive advance of the desert, swallowing what were once farms, and the shrinking of Lake Chad, which once seemed so vast that when she crossed it in a hovercraft, she said it was "like I was flying to England."

"Now," she said, "it’s a puddle."

Mohammed, 54, has served as the top U.N. diplomat responsible for corralling countries to commit to a spectacularly ambitious set of global development goals, meant to save the planet and its most vulnerable people. Known as the Sustainable Development Goals, or Agenda 2030 after the deadline for meeting them, or often just as the Global Goals, they were adopted Friday at the opening of a three-day summit meeting in New York, which 154 heads of state and government were due to attend.

The goals apply to all countries, rich and poor, and they are fleshed out with 169 specific targets for action. The estimated price tag for achieving them is $3 trillion, and few people think it will be easy.

"The low-hanging fruit have almost all been picked," said Jim Kim, president of the World Bank.

Though the goals are not legally binding on any country, they gain moral force from having been adopted by consensus after three years of lengthy negotiations. The sticking points along the way included objections from Qatar, the Vatican and others over access to sexual and reproductive health services, and pushback from the United States and others over reducing inequality. There were, and still are, fierce disagreements over tax loopholes used by multinationals in poor countries, and the need to root out corruption.

One big piece of the process remains unfinished: deciding how best to measure whether the targets are being met, so citizens can hold their governments to account. For the sanitation goal, for example, the yardstick might be how many toilets a country has built, or how many homes are connected to a water supply.

"The one knot we haven’t tied is the accountability," Mohammed said. The deadline for doing so is in March.

The new goals follow and expand on an earlier list, the Millennium Development Goals, adopted by the United Nations in 2000. Those were mainly intended for developing countries, and some of them have been met. The number of people living in dire poverty around the world has been cut in half, for instance, largely because of China’s rapid economic growth. Malaria deaths have been sharply reduced, but the world has missed its target of reducing child mortality by two-thirds.

Bill Gates, who has pressed world leaders to keep health at the center of the new goals, said in a telephone interview that each country will have to decide for itself which of the 17 new goals to make a priority. His charitable foundation will spend nearly $3 billion a year to help poor countries achieve the new goals, and the list gives him a template for talking to presidents and prime ministers about what remains to be done.

Gates said the previous goals "really got people to measure things better," laying a foundation to pursue the new ones: "When I meet with heads of state, I can show them how they’re doing."

A lot of effort has gone into publicizing the initiative, including enlisting young bloggers to get the word out and projecting graphic icons for each goal on the facade of the U.N. headquarters this week. "You can’t fight for your rights if you don’t know what they are," said filmmaker Richard Curtis, who has helped with the effort.

To their champions, including Mohammed, the 17 goals are aspirational. To critics, they are unrealistic, even wasteful. "Having 169 priorities is the same as having none," said Bjorn Lomborg, a visiting professor at Copenhagen Business School and runs the Copenhagen Consensus Center, a think tank based in Denmark. He tried to persuade the United Nations to pare the list of targets. "This laundry list of aspirations tries to please everyone, and yet will end up doing much less for the most vulnerable people," Lomborg said.

Asked whether the list of 17 goals was too long, Gates offered a scriptural analogy: "When you read the Bible, you say they could have edited out a few pages," he observed, but "the core messages are there."

Still, 17 goals are a lot to keep in mind. U.N. Secretary-General Ban Ki-moon relies on a laminated cheat sheet that he keeps in his suit pocket.

Mohammed has always had a foot in several worlds. The child of a Nigerian father and an English mother, she attended primary school in Maiduguri, which is now in the heart of Boko Haram territory in Nigeria, and later studied in Britain; she speaks with a plummy English accent and favors Nigerian fashion, usually wearing a long skirt, a headwrap, and a shawl draped around her shoulders.

She advised the Nigerian government on how to meet the previous goals before taking her current post in 2012, and said that at the end of the year, when her term ends, she plans to return to Nigeria, where she has a home in the capital, Abuja.

Boko Haram violence has claimed the lives of several of Mohammed’s friends and relatives, and she said she could not help noticing that the boatloads of desperate people who have tried to get to Europe in recent months include many fleeing the Sahel.

"These goals," she said, "have got to come back and make a difference."

Breakdown of U.N. Sustainable Development Goals

The Sustainable Development Goals adopted by the United Nations at a summit meeting in New York on Friday lay out a sweeping vision for improving the lives of people all over the world over the next 15 years.

They replace and expand on the U.N.’s previous road map, the Millennium Development Goals that were adopted in 2000. Those were aimed mainly at developing countries, and met with widely varying degrees of success.

The new global goals are more ambitious, and are meant to apply to every country, not just the developing world. Stated in broad terms, the goals are accompanied by 169 specific targets meant to advance the goals in concrete ways. Most are meant to be achieved by 2030, though some have shorter deadlines.

Here are the 17 new goals:

1. End poverty in all its forms everywhere.

2. End hunger, achieve food security and improved nutrition, and promote sustainable agriculture.

3. Ensure healthy lives and promote well-being for all at all ages.

4. Ensure inclusive and quality education for all and promote lifelong learning.

5. Achieve gender equality and empower all women and girls.

6. Ensure access to water and sanitation for all.

7. Ensure access to affordable, reliable, sustainable and modern energy for all.

8. Promote inclusive and sustainable economic growth, employment and decent work for all.

9. Build resilient infrastructure, promote sustainable industrialization and foster innovation.

10. Reduce inequality within and among countries.

11. Make cities inclusive, safe, resilient and sustainable.

12. Ensure sustainable consumption and production patterns.

13. Take urgent action to combat climate change and its impacts.

14. Conserve and sustainably use the oceans, seas and marine resources.

15. Sustainably manage forests, combat desertification, halt and reverse land degradation, halt biodiversity loss.

16. Promote just, peaceful and inclusive societies.

17. Revitalize the global partnership for sustainable development.

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