The extraordinary risk-management discipline that developed out of the writings of the University of Chicago's Harry Markowitz in the 1950s produced insights that won several Nobel prizes in economics. It was widely embraced not only by academia but also by a large majority of financial professionals and global regulators.
But in August 2007, the risk-management structure cracked. All the sophisticated mathematics and computer wizardry essentially rested on one central premise: that the enlightened self-interest of owners and managers of financial institutions would lead them to maintain a sufficient buffer against insolvency by actively monitoring their firms' capital and risk positions. For generations, that premise appeared incontestable but, in the summer of 2007, it failed. It is clear that the levels of complexity to which market practitioners, at the height of their euphoria, carried risk-management techniques and risk-product design were too much for even the most sophisticated market players to handle prudently.