They came in their Jimmy Choos, their diamonds and their pearls. But these women meant business.
As the (mostly male) leaders of the world's largest economies arrived in the US for the Group of 20 meeting, 300 of the globe's most influential women gathered in New York on Wednesday night determined to help tackle one of the most pressing but least noticed issues holding back global economic recovery: maternal health.
The dinner was hosted by Queen Rania Al Abdullah of Jordan, Wendi Murdoch, wife of Rupert Murdoch, chief executive of News Corporation, owner of The Times, and Indra Nooyi, chief executive of Pepsi.
The guest list read like the roll call for the biggest ever girls-only celebrity party. In addition to G20 wives, chief executives and chairwomen, guests included actresses (Nicole Kidman), models (Naomi Campbell), diplomats and politicians, charity workers, writers and the simply well-connected.
This was no ordinary party, however. Maternal health is the mother of all economic issues and a key barometer of national well-being.
PepsiCo's Indra Nooyi said in a speech. "Throughout the world the greatest unexploited economic resource is the female half of the population." Countries such as China have prospered and achieved economic growth partly by bringing women into the economy, she added.
And yet, as Sarah Brown, wife of the British Prime Minister, said in a keynote address, more than half a million women worldwide die each year from pregnancy-related causes, most of them preventable. Millions more suffer injuries and develop lifelong disabilities.
Reducing these numbers could bring real economic gains by ensuring that women remained alive to feed, vaccinate, educate and nurture the next generation, as well as make their own economic contribution.
Mrs Brown called on world leaders at the G20 meeting in Pittsburgh today and tomorrow to put maternal health high on their agenda. This would help to ensure that the United Nations' Millennium Develpoment Goals outlined in 2000, which include reducing maternal deaths by 75 per cent, could be achieved by 2015.
The issue had to take centre stage, she said. "We have let so many girls and women down so very badly over so many years."
She encouraged the women present to get involved in the White Ribbon campaign for maternal health, using their influence in whatever way they could. She also encouraged tham to make a cash donation to the campaign equivalent to the value of the next item they bought themselves, be it a dress, a car . . . or a house.
The dinner was more than just a talking shop. It is part of a continuing campaign and was the fourth dinner of its kind.
The first was held in at the World Economic Forum in Davos in 2008 to discuss the UN Millennium Development Goals. It became the most talked about event at the forum that year - partly because Bono, Rupert Murdoch and Google's Sergey Brin and Larry Page served the drinks and pudding.
The interest and success of these dinners has led to a powerful coalition of women, from Sarah Brown and Carla Sarkozy to leading activists including Melinda Gates, wife of Microsoft founder, Bill.
By attending the dinners, First Ladies and ministers from US to Canada to India to Sierra Leone have ensured that their governments have begun to take notice and start taking action.