Ireland's RTÉ National Symphony Orchestra is the concert music orchestra of Radio Television Ireland. Formerly the National Symphony Orchestra of Ireland, the ensemble began with the formation of a national radio channel, based in Dublin, in 1926. The station hired staff musicians, who often played together on the radio and in concert as a chamber orchestra. String players from the radio, wind players from the Army School of Music, and other musicians played as the Dublin Philharmonic Society under the direction of Col. Fritz Brase, head of the Army School from 1927.

In 1947, the broadcasting authority, now called Radio Éireann (Radio Ireland), expanded its orchestra by opening its membership to musicians from all over Europe and renaming the group the Radio Éireann Symphony Orchestra. Its initial conductor was Captain Michael Bowles. After he retired in 1948 (he had been conducting the small predecessor or the RÉSO for several years), the new orchestra drifted without a permanent conductor, but played for such major conductors as Jean Martinon and Hans Schmidt-Isserstedt. Finally, in 1953, the orchestra found a principal conductor in Milan Horvat, who remained until 1961. Also in 1953, Ireland added television to its broadcasting service. The name of the government body (in English) established by a new broadcasting act in 1960 was the Irish National Public Service Broadcasting Organisation, and the on-air service became Raidió Teilifís Éireann (RTÉ). The orchestra became known as the RTÉ Symphony Orchestra, and it was, de facto, the national orchestra of Ireland and the main city orchestra of Dublin. Its chief conductor from 1962 was Tibor Paul. He was succeeded by Albert Rosen, Colman Pierce, Bryden Thomson, and Jànos Fürst.

In 1981, the orchestra found a new concert home when the National Concert Hall opened in Dublin. At about the same time, it expanded its broadcasting activities. Until 1979, RTÉ had run only one radio channel and one television channel. In 1979, it established more channels, including an arts station called FM3, which aired numerous concerts by the RTÉSO. In 1989, the orchestra was expanded to the size of a large symphony orchestra, and it was renamed the National Symphony Orchestra of Ireland. Its principal conductor was George Hurst. Kaspar de Roo took that position in 1994, followed by Alexander Anissimov and Gerhard Markson. In 2005, the orchestra changed names again, officially becoming the RTÉ National Symphony Orchestra. As of 2018, the principal conductor post was vacant, but Nathalie Stutzmann was under contract as principal guest conductor, and the orchestra had a large roster of world-class guest conductors to draw on.

The RTÉ National Symphony Orchestra has championed contemporary music with Irish premieres including Thomas Adès' Totentanz, Wolfgang Rihm's Verwandlung 4, Kaija Saariaho's Circle Map, and Wave Movements by Bryce Dessner (of the rock band the National) and Richard Reed Parry (Arcade Fire). The orchestra also plays a major role in music education in Ireland, with a full schedule of school concerts and youth events. The orchestra has recorded extensively for the Naxos label, issuing a recording of Poulenc's ballet Les biches in 2018. The following year saw the release of Orchestrated, a collaboration with Irish folk legend Mary Black. ~ James Manheim & Joseph Stevenson, Rovi