The Government has formally recognised multi-denominational body Educate Together as a second-level patron.
The group, which has 58 schools at primary level, has long campaigned for a new type of secondary school to cater for the growing number of pupils coming out of their primary schools.
At the body's AGM in Gorey, Education Minister Ruairi Quinn said he wanted recognition for new second-level schools in keeping with the Government's commitment to plurality.
"I am finalising proposals to bring to Cabinet so that I can set about implementing this Government commitment shortly," Mr Quinn said.
Educate Together applied to open its first secondary school in 2007. It caters for 13,000 primary school pupils.
Paul Rowe, Educate Together chief executive, welcomed the announcement and promised the first secondary school in the near future.
"With the need to establish up to 20 new post-primary schools over the next five years, Educate Together now has concrete expectations of the first Educate Together second level school opening its doors in the very near future," he said.
Mr Rowe also called for a review of recently announced cuts in student support services and said the government should seek greater savings in education administrative overheads, particularly at second level.
"Today's announcement will herald significant change in Irish education," he said. "However for our children to prosper in a reformed second level system, their primary education must also be protected. Our financial challenges are not of our children's making and we should not seek the savings we need to make at the expense of frontline education services."
Educate Together has 73 new school applications lodged with the Department of Education and will open new primary schools in Blanchardstown West and Tyrellstown this September.