Two decades ago, on October 27, 1986, the old-fashioned gentleman’s club that was the City of London was democratised by a sequence of changes that have come to be known as Big Bang. But that date was neither the beginning nor the end of the process. (Indeed, many believe that MiFID, the dreaded Markets in Financial Instruments Directive, is simply the next stage of Big Bang – just 20 years later.) Many years of earnest debate and political wrangling had led up to that event and several tumultuous years of changes were to follow. While the City has been utterly transformed, the scale of the changes was probably not foreseen on the day of Big Bang – and certainly not by the politicians who put the train of events in motion. Nor is it absolutely clear whether Big Bang was (as conventional wisdom has it) truly revolutionary, or whether it was just one evolutionary step in a process that had begun years earlier in the wholesale markets – and that would have occurred regardless of decisions taken by City grandees in the Stock Exchange’s boardroom.