The Four Courts in Dublin is the Republic of Ireland's main courts building. It is the location of the Irish Supreme Court, High Court and Central Criminal Court.

The Four Courts along the River Liffey quayside. Part of the original Gandon-designed interior decoration of the dome, lost in the 1922 destruction.

The Four Courts was built between 1796 and 1802 by renowned architect James Gandon, who built The Custom House. The building originally housed the four courts of Chancery, King's Bench, Exchequer, and Common Pleas, hence the name of the building. A major revision in the legal structures in the late nineteenth century saw these courts replaced, but the building retained its historic name. The new courts system remained until 1924, when the new Irish Free State which had replaced British rule introduced a new courts structure, replacing the old High Court of Ireland, the Lord Chief Justice of Ireland and the Lord Chancellor of Ireland with a new Supreme Court presided over by the Chief Justice and a High Court of Justice, presided over by the President of the High Court.

The Four Courts were seized by Commandant Ned Daly's 1st Battalion during the Easter Rising in 1916. They survived the bombardment by British artillery that destroyed large parts of the city centre, however in 1922 they were gutted as part of the Irish Civil War. Republican rebels who opposed the Anglo-Irish Treaty, seized the building. The new Irish government under the Chairman of the Provisional Government and Commander-in-Chief of the Irish Army, Michael Collins was forced to attack the building to dislodge the rebels. In the process of the bombardment the historic building was destroyed. Most dramatically however, when withdrawing, the rebels deliberately boobytrapped the Public Records Office which was located at the rear of the building. They also boobytrapped its priceless Irish archives, which were stored in the basement of the Four Courts. Nearly one thousand years of priceless archives were destroyed by this act, which is still regarded with infamy.

For a decade, the old courts system until 1924, then the new Free State courts system, was based in the old viceregal apartments in Dublin Castle. In 1932, a rebuilt and remodelled Four Courts was opened again. However much of the decorative interior of the original building had been lost and, in the absence of documentary archives (some of which had been in the Public Records Office and others of which were among the vast amount of legal records lost also), and also because the new state did not have the funds, the highly decorative interior was not replaced. Two side wings were rebuilt further from the river to undo the problem caused by excessively narrow footpaths outside the building. However that change, and the removal of chimney-stacks, has removed some of the architectual unity and effect planned by Gandon in 1796.

In 1937 a new constitution, Bunreacht na hÉireann, introduced a remodelled courts system. Again the highest court was called the Supreme Court, with a slightly changed High Court (minus the words 'of Justice'). Though in the early 1990s, the then Irish Chief Justice suggested building a new purpose-built building to house the Supreme Court, leaving the other courts in situ, the Supreme Court for the moment remains in the Four Courts.

Though one of Dublin's most spectacularly beautiful buildings, the Four Courts was for many decades poorly maintained, with unattractive additional buildings added on at the back. The interior also was poorly maintained and decorated. The recent establishment of the Irish Courts Service, which took over the running of the courts system and the maintenance of courts buildings from the Department of Justice, has raised hopes that the building may once again be restored to its true grandeur. Its exterior still shows the effects of the events of 1922, with its facade containing bullet holes, which deliberately were not removed to remind people of its complex history.