The government regulator for gas and electricity markets in Great Britain.
Ofgem's main aim is to protect the interests of existing and future electricity and gas consumers, by:
Promoting value for money
Promoting security of supply and sustainability, for present and future generations of consumers, domestic and industrial users
The supervision and development of markets and competition
Regulation and the delivery of government schemes.
They work with, but are independent of, government, the energy industry and other stakeholders within a legal framework determined by the UK government and the European Union.
Source and further information: Ofgem website