Ordnance Survey of Northern Ireland (OSNI) was the official mapping agency of Northern Ireland. The agency ceased to exist separately on 1 April 2008 when it became part of Land and Property Services, an executive agency of the Northern Ireland Department of Finance and Personnel, along with the Rate Collection Agency, the Valuation and Lands Agency, and the Land Registry.
It was an Executive Agency within the Department of Culture, Arts and Leisure in the Northern Ireland Executive.
The Ordnance Surveys of Northern Ireland, Great Britain and the Republic of Ireland share a common heritage: the British Ordnance Survey (OS) ceased to map Ireland just before the creation of the Irish Free State in 1922 (the Partition of Ireland having already taken place in May 1921 with the creation of Northern Ireland). The new Ordnance Survey of Northern Ireland (OSNI) officially came into existence on 1 January 1922, while the new Ordnance Survey of Ireland (OSI) came into being slightly later, on 1 April 1922.
The vast majority of OSNI's income came from the licensing of its digital mapping data, which, because of the long history of mapping in Ireland (see Ordnance Survey) is amongst the most detailed and comprehensive in the world. Digital products range from the Large Scale (1:1250 urban and 1:2500 rural) vector database, 1:10,000 raster mapping derived automatically from the L/S vector, 1:50,000 and 1:250,00 vectors, 1;10,000 orthophotography, 1:25,000 leisure maps, the 1:50,000 raster series, 1:250,000 Ireland North raster, street maps of the main conurbations, as well as paper derivatives of all the raster products.