UK Visa Rules
Citizens of European Economic Area (EEA) countries (EU plus Liechtenstein, Norway and Iceland) do not require immigration clearance and are free to seek and take work in the UK without the need to apply for a work permit or a residence permit.
Note: If the dependants of an EEA national are non-EEA nationals, they do require immigration clearance from a British Embassy.
Commonwealth citizens may be able to work permit free in the UK provided that prior entry clearance is obtained from the British Embassy in the country where the person is currently living.