Edition and translation of a copy of a vastly significant document for our understanding of fourteenth-century England, long believed lost.In the summer of 1376 a spirit of reform was abroad in the city of London. A number of measures were taken to make those who were elected to govern the city more responsible to its citizens as a whole. A committee was set up to examine the ordinances at the Guildhall and present to the Commonalty those that were "profitables" and those that were not. Two years later, the committee produced a volume known officially as the Liber de Ordinancionibus, but popularly as "The Jubilee book", because it had been initiated in the jubilee year of Edward III's reign. But the reforming measures introduced in the book caused so many controversies and disputes that eventually, in a bid to restore order in the city, in March 1387 the "Jubilee Book" was taken outside the Guildhall and publicly burnt. Historians have long debated the possible contents of this contentious but hugely significant volume, widely believed to be lost. However, recently a fifteenth-century copy of the "Jubilee Book", possibly of an earlier draft put together in the course of the two years, but superseded by the final version, was discovered in a manuscript held at Trinity College Cambridge (Ms O.3.11).