The Christian Brothers College at Monkstown, Dun Laoghaire, County Dublin, is situated on the grounds of an 18th-Century Gentleman’s residence, Monkstown Park.

On January 1st. 1857, the Christian Brothers opened a school at Eblana Avenue in Dun Laoghaire. This was just ten years after the Great Famine, and emigration was rife. The school at Eblana prospered to an extent that it became impossible to accommodate both primary and secondary departments in the 19th. Century buildings. Accordingly, in 1949, the Brothers purchased the nearby estate of Monkstown Park, which had been most recently occupied by a Protestant school. The secondary department, with the exception of the commercial stream, moved to the house at Monkstown in 1950, and extended the neo-classical house built by Charles Haliday in 1843. In 1987, the school was further extended to include new offices, a cafeteria, a staff room and a technology department. The Edmund Rice Oratory, opened in 1994. The latest build, opened in March 2014, includes 4 extra Science labs, a Design Communication Graphics room, an Art room, along with 6 new classrooms.

The school motto is Certa Bonum Certamen (CBC) or fight the good fight and the school colours are red, black and yellow. From the start, the boys played Rugby as the main competitive team sport of the school and for a small school have achieved relatively great success, winning the Leinster Senior Cup in 1976 and reaching the finals in 1984 and winning the League Cup at Junior Level in 1998.

Famous past pupils include John O’Shea, well known in Ireland for the charity which he founded (GOAL) along with the playwright Bernard Farrell; actor Rory Nolan; footballer Andy Keogh; GAA footballer Michael Fitzsimons and Frank McCabe, managing director of Intel in Ireland.