The three general lighthouse authorities are the agencies primarily responsible for aids to navigation in the United Kingdom and Ireland. They are divided into regions as follows:
Local lighthouse authorities (LLA) are ports, harbours, or other parties providing navigational aids in a locality as part of its facilities. These local authorities subscribe to the general lighthouse authority's policy on the correct maintenance and provision of such equipment.
Funding for the three GLAs is primarily collected through light dues, which are pooled in the General Lighthouse Fund and dispersed to the three authorities. The Irish government also makes a contribution to the GLF.
The powers of Trinity House and the Northern Lighthouse Board are established in the Merchant Shipping Act 1995. These include the inspection of aids to navigation provided by local lighthouse authorities, and the levying of light dues on vessels to fund their work. The Dublin Port Act of 1867 established the Commissioners of Irish Lights as successor to the Corporation for Preserving and Improving the Port of Dublin as the agency responsible for all Irish coastal lights.