Syrians arriving on the Greek island of Lesbos are part of the largest flow of refugees since World War II. The challenge for the U.N. is to find the funds and political will to address refugee needs while tackling the newly ratified Sustainable Development Goals. Angelos Tzortzinis/AFP/Getty Images hide caption

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Breaking bricks is one of the lowest-paying jobs in Bangladesh. This photo was shot at a brick kiln in the Dhaka District, home to the capital city of Dhaka. Paul Joseph Brown hide caption

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United Nations

Syrian refugees continue to arrive in Jordan, where they are greeted by authorities and sent to refugee camps and temporary settlements. Khalil Mazraawi/AFP/Getty Images hide caption

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Delegates took their seats during the plenary session at the Bonn climate change conference on March 10, 2014. Negotiations resume this week; by the end of the year, the U.N. hopes to have forged a new global agreement. UNclimatechange/Flickr hide caption

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Babacar Gaye has been forced to resign from his post leading the U.N.'s peacekeeping mission in the Central African Republic. He's seen here in 2012, when he led the U.N.'s force in Syria. Hazim/Xinhua /Landov hide caption

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Iranian workers transfer goods from a cargo container to trucks in May at the Kalantari port in Chabahar, Iran. The removal of sanctions on Iran under a recent deal with world powers is expected to boost the country's economy, but the agreement was carefully constructed to quickly put those sanctions back in place if Iran is suspected of violations. Atta Kenare/AFP/Getty Images hide caption

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Street children sleep on a discarded mattress on a center island near a road crossing in Manila, Philippines, in April. After 15 years of the Millennium Development Goals, Asia as a region has had the fastest progress, reports the U.N., yet hundreds of millions of people there remain in extreme poverty. Jay Directo/AFP/Getty Images hide caption

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Syrian refugees wait to be registered at the port of Mytilini in Greece following a 6km-long march. Louisa Gouliamaki /AFP/Getty Images hide caption

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