It was established in 1870 at Harcourt Street before moving to Rathgar in 1971.

It amalgamated with The Diocesan School for Girls in 1974, becoming co-educational.

The school offers a range of sports including badminton, cricket, cross country, hockey, rugby and tennis.

[3] In 2009, it was noted as the school with the highest rate of progression to third-level education.

[4] It is owned and overseen by the Erasmus Smith Trust.