After many years of a rich history in Madison and along the shoreline, OLM Prep has returned to its roots. On September 4, 2018, Our Lady of Mercy School reopened its school in the same exact tradition it began in 1954, as Our Lady of Mercy Preparatory Academy (OLM Prep), as a successor school, now located at 20 Island Avenue, Madison, CT. OLM Prep is an independent private school which teaches to the Catholic-based tradition and is open to all faiths, just as Our Lady of Mercy School was until 2006. 

In 1954, the Sisters of Mercy began an independent private school, unaffiliated and separate from the archdiocese and the local parish, grade by grade in the Emanuel House, until the completion of the school on Neck Road in 1962 and was called Our Lady of Mercy Country Day School. This was a Novitiate for the Sisters of Mercy as they were a teaching order where the novices taught the students in the Catholic-based tradition to be “Christ in the World”.

Throughout the years these students consistently excelled, academically placing at many fine secondary schools, such as Choate Rosemary Hall, Hamden Hall, Hopkins Day School, Portsmouth Abbey, Pomfret, Sacred Heart Academy, Mercy High School, Laurelton Hall, Notre Dame, Xavier, Miss Porter's School, as well as enrolling in the public high schools in their respective towns.

The Archdiocese of Hartford took over the school from the Sisters of Mercy in 2006, when the school became a parochial/parish school controlled by their education department. In January 2018, the archdiocese decided they no longer wanted a Catholic school in Madison.​

OLM Prep welcomes all those who wish to learn more about the school and is continuing the academic richness of an independent Catholic-based school that it has been for many decades.