The role played by the House of Commons in the legislative process has been steadily changing since the Reform Acts of the nineteenth century. Previously, most of the Commons' legislative work consisted in passing private measures initiated and introduced by individual Members of Parliament concerned with, and knowledgeable about, local issues which required change. The growth of an increasingly vocal and educated mass electorate, the pressures of mass-membership political parties, and the increasing specialization of an industrial society, all increased the need for wider legislation, particularly for public social measures, and its initiation passed from the hands of individual members to the Government Parliament as a law-making body moved towards a more formal constitutional and legal role. Its twentieth century task is more often the legitimation of legislative changes originating elsewhere.