Over 40 world leaders, including former Prime Minister Gordon Brown, have called for a “powerful shift” in world economic policy “to address rising threats of poverty, disparity and environmental breakdown,” in reaction to the news that the next fifty years could see the emergence of the world’s first trillionaires while the majority of the world face destitution. In an open letter sent by the Club de Madrid group, a conference of former Prime Ministers and Presidents, they correctly identify that the world’s economic model is “outdated,” and that, “trillions of dollars exist for financing development – but too much public money is captured by private power,” calling for taxation on high-net-worth individuals.