Government policy to encourage competition. This may be concerned with the structure of industries, or with the behaviour of firms within them. As regards the structure of industries, governments have sometimes favoured monopolies, as with the UK postal service, or regulated entry, as with telephones, television, and public transport, and have sometimes restricted them via monopoly legislation and the setting up of the UK Monopolies and Mergers Commission, now the Competition Commission. As regards the conduct of firms, governments have legislated against various practices which were thought to inhibit competition, including retail price maintenance, exclusive dealing, and refusal to supply. In the UK the Office of Fair Trading is responsible for enforcing these rules. On the other hand, governments have supported self-regulatory bodies, which are sometimes held to operate against competition between firms in their industries and against entrants to them. See also antitrust.