Christine Lagarde, head of the International Monetary Fund, told the assembled global elite she had been opposed to quotas until a moment early in her career when she was told she would not progress because she was a woman.
"I soon realised that unless we had targets, if not quotas, there was no way" to make headway, she said.
The sole male member of the panel, Nissan-Renault Chief Executive Carlos Ghosn, said he had introduced quotas at his firm in Japan when he realised that only two percent of his management team were women.
"We have now reached the ridiculous figure of eight percent, which is three times more than the corporate average in Japan," Ghosn said.
"A quota leads to action. Action leads to training," he said.
Facebook Chief Operating Officer Sheryl Sandberg said women also had to contend with cultural and structural barriers in the workplace that held them back.
"Leadership is associated with masculine expectations," she said. "When women do the things that make them leaders, we don't like them."
Organisers of the World Economic Forum in Davos, which brings together 2,500 of the world's top political and business leaders, said that 16 percent of this year's participants were women.
This was a slight drop from the 17 percent who attended in 2013 but a rise from the nine percent in 2002.
Last year, a trio of topless activists from Femen targeted the cosy gathering, baring their breasts in the bitter cold of the snowy Swiss ski resort.