Veteran Labor Senator Jacinta Collins has been confirmed as the new head of the powerful National Catholic Education Commission.
Ms Collins, who left politics on Thursday after first entering parliament in 1995, will start her new job next week.
"In the parliament, I was a strong advocate for fair funding for all schools and I will continue to be a strong voice for the needs of Catholic schools, teachers and students," she said in a statement on Friday.
Ms Collins held a range of frontbench roles during her time in parliament, including portfolios in education and early childhood.
"Her parliamentary knowledge and a strong commitment to the values that underpin Catholic schools make her the ideal person to lead the NCEC," its chairman Greg Crafter said.
Ms Collins will be responsible for lobbying on behalf of roughly 770,000 students in Catholic schools and their families, as well as more than 90,000 people who work in the sector.
Ms Collins is a leading figure in Labor's socially conservative faction known as the "Shoppies".
In her valedictory speech, she insisted the group still wielded serious influence in the party, despite Labor increasingly adopting progressive social stances on issues like same-sex marriage.
"I do not represent a dying breed in the Labor Party. Those who come to our great party - or broad church - from a base of Christian social principles are not disappearing," she told parliament.
"In some respects, we are stronger than during some periods over which I've served over the past two decades - just look at the recent euthanasia debate."
In August, she combined with faction allies Don Farrell, Helen Polley, Chris Ketter, and Deborah O'Neill to defeat legislation which would have given territories the right to make assisted-suicide laws.
"It serves the interest of some of those on the far-left and the far-right of politics to dismiss and diminish us, but I thank the many people over a wide spectrum who do not," Senator Collins said.
She pointed to Labor's commitment to protecting religious freedoms in schools as further evidence her grouping could still advance their interests.
Ms Collins will be replaced in the Senate by union official Raff Ciccone.
