Saint Mary's College C.S.Sp. (Congregatio Sancti Spiritus) is a voluntary boys' primary and secondary school run by the Congregation of the Holy Spirit and located in Rathmines, Dublin, Ireland. The school was founded in 1890, closed in 1916, and then reopened in 1926 (from 1917 until 1926 the St. Mary's operated as a House of Philosophy for the Spiritans, before it moved to Blackrock.). The school colours are blue and white.