The School was founded in 1990 when it opened its doors as South City School Project with 39 children enrolled in six classes. The first principal was Paddie Murphy. The first premises of the school was in St. Mary’s, Church of Ireland School in Crumlin on a shared campus. The building was burnt in March 1993 and the school was rehoused in Rathfarnham in September of that year. The school changed its name to Rathfarnham Educate Together (RETNS) in 2001.