Ofcom, the Office of Communications, is the UK regulator of the broadcasting and telecommunications industries.
Its main duty in telecoms regulation is to ensure the wide provision of services to consumers (e.g., by encouraging the roll-out of new services), license and regulate network operators and promote competition.
In radio and television it is also responsible for the quality of material broadcast, preventing the broadcast of offensive material and preventing unfairness and infringements of privacy.
As media and telecoms converge the regulation of content imposed on broadcasters will also increasingly apply to some of the operations of telecoms companies. This is why the duties of the former telecoms regulator Oftel were combined with those of regulating the media.
The primary importance of Ofcom to investors is the power it has over the telecoms and media companies it regulates. Changes to Ofcom policy can have drastic effects. It both sets the framework in which media and telecoms companies operates and it can impose pricing and other restrictions on individual companies.
Ofcom is also a very useful source of information. It gathers detailed statistics on the industries it regulates which are invaluable to investors. There are other useful sources (such as Rajar), but Ofcom publishes more detailed information on its publicly accessible website than any other single source.