The Official Languages Act 2003 is an Act of the Oireachtas of Ireland. The Act sets out rules regarding use of the Irish language by public bodies; established the office of An Coimisinéir Teanga to monitor and enforce compliance by public bodies with the provisions of the Official Languages Act; and made provision for the designation of official Irish-language versions of placenames and the removal of the official status of English placenames in the Gaeltacht. The Act is being implemented on a phased basis.

A Gaeltacht is a district of Ireland, either individually or collectively, where the Irish government recognises that the Irish language is the predominant vernacular, or language of the home. The Gaeltacht districts were first officially recognised during the 1920s in the early years of the Irish Free State, following the Gaelic revival, as part of a government policy aimed at restoring the Irish language.