The Office of Public Works (OPW) (Irish: Oifig na nOibreacha Poiblí; legally the Commissioners of Public Works in Ireland) is a major Irish Government agency, which manages most of the Irish State's property portfolio, including hundreds of owned and rented Government offices and police properties, oversees National Monuments and directly manages some heritage properties, and is the lead State engineering agency, with a special focus on flood risk management. It lies within the remit of the Minister for Public Expenditure, Infrastructure, Public Service Reform and Digitalisation, with functions largely delegated to a Minister of State at the Department of Public Expenditure, Infrastructure, Public Service Reform and Digitalisation with special responsibility for the Office. The OPW has a central role in driving the Government's property asset management reform process, both in respect of its own portfolio and that of the wider public service. The agency was initially known as the Board of Works, a title inherited from a preceding body, and this term is still sometimes encountered.
The second oldest state agency in all of Ireland, the OPW subsumed the functions of the Commissioners and Overseers of Barracks (the Barrack Board) and the Board of Works / Civil Buildings Commissioners (which two agencies had in turn taken on the functions of the Office of the Surveyor General in 1762), the Directors-General of Inland Navigation (which had taken on the functions of the Fisheries Commissioners), and some functions of the Postmaster-General, and those of the Public Works Loans Commissioners.