As the Independence Mission Schools network prepares to celebrate its five-year anniversary in 2017, the nonprofit that manages 15 inner-city Catholic schools announced Monday that it is launching a national search to fill a new position of CEO.

Officials say it's part of a transition plan to move the network beyond the start-up phase and make it a model for urban Catholic schooling.

"We are really at the forefront in terms of size and impact because of the high poverty level in Philadelphia," Anne McGoldrick, president of Independence Mission Schools, said Friday.

Board member Mary McDonald, who helped create the Jubilee Schools in Memphis and reopened 10 urban Catholic schools there, will lead the search.

McGoldrick, who has been the top official in the central office, said the network has evolved and needs a CEO "to continue the momentum." She said the board hopes to announce a CEO in early summer.

The network was created in 2012 to save and support endangered Catholic schools in impoverished neighborhoods. The mission concept is based on the successful model of St. Martin de Porres in North Philadelphia, which increased enrollment, stabilized finances and added programs.

St. Martin, 13 other former parish schools in Philadelphia, and St. Cyril of Alexandria in East Lansdowne are in the network.

The schools are open to children of all faiths. Tuition this academic year is $4,500. Most families pay about $2,000 and receive aid to cover the remainder.

The network, which has increased scholarship funds from $2 million to $8 million, is overseen by a small central office staff based at St. Malachy School in North Philadelphia.

Since 2012, enrollment has grown by 1,000 students across the network, and the schools now educate nearly 4,800 students.

McGoldrick, who had worked at a private equity firm and originally joined Mission Schools as the chief financial officer to help launch the network, plans to step down as president and return to the private sector at the end of 2017.

She said she expected to remain involved with the schools.

martha.woodall@phillynews.com 215-854-2789 @marwooda