The end-products of legislation are easily recognized. They are Acts of Parliament as published in the Statutes Revised, and the contents of the collected annual volumes of Statutory Instruments. The modern legislative process in Britain is a multi-stage process, in which different criteria and constraints operate at each level. The governing procedures associated with the modern process are those of consultation by the executive with organized interest groups, followed by Parliamentary investigation of the general and special merits of the proposal. Great social and economic changes were brought about piecemeal by private legislation initiated by outside interests, and applying to particular areas, particular proprietors and particular authorities. The legislative process in Britain is now complex: it comprises deliberative, Parliamentary and administrative stages, over all of which executive political influence is predominant. Legislation is now an almost exclusively executive function, modified, sometimes heavily, by practices of group and Parliamentary consultation.