This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book shows, briefly, how in the nineteenth century the procedures of private bill legislation gave way, because of changed administrative and political circumstances, to legislation by public general act. It sets out broadly the sources of legislative policy in Britain. The book deals with a marked phenomenon in the process of legislation—the extent to which the government consults at the preparatory stages of bills and statutory instruments with interested and affected parties. The book deals with the legislative structure of the cabinet, and sets out the conventional relationships which have emerged between pressure groups, departments and the cabinet in the preparation of legislation. It contains some discussion of recent proposals for parliamentary reform.