Pope Francis has introduced a landmark reform that will allow any baptised lay Catholic, including women, to head most Vatican departments under a new constitution for the Holy See's central administration.
For centuries, the departments have been headed by male clerics, usually cardinals or bishops, but that could change from 5 June when the new charter takes effect after more than nine years of work.
The 54-page constitution, called Praedicate Evangelium (Preach the Gospel), was released on the ninth anniversary of Francis' installation as pope in 2013, and replaces one issued in 1988 by Pope John Paul II.
Its preamble says the "pope, bishops and other ordained ministers are not the only evangelisers in the Church", adding that lay men and women "should have roles of government and responsibility" in the central administration, known as the Curia.
The principles section of the constitution says "any member of the faithful can head a dicastery (Curia department) or organism" if the pope decides they are qualified and appoints them.
Under the 1988 constitution, the departments - with a few exceptions - were to be headed by a cardinal or bishop and assisted by a secretary, experts and administrators.
The new constitution makes no distinction between lay men and lay women, though experts said at least two departments - the department for bishops and the department for clergy - will remain headed by men because only men can be priests in the Catholic Church.
The department for consecrated life, which is responsible for religious orders, could conceivably be headed by a nun in the future, the experts said. It is now led by a cardinal.
In an interview with Reuters in 2018, the pope said he had short-listed a woman to head a Vatican economic department, but she could not take the job for personal reasons.
The new constitution said the role of lay Catholics in governing roles in the Curia was "essential" because of their familiarity with family life and "social reality".
Francis also merged some offices, created a new one to oversee charity efforts, and set up a new order of importance.
The Pontifical Commission for the Protection of Minors, which includes lay people and abuse victims, appears to have been given more institutional influence by being incorporated into the doctrinal department, which decides on sanctions for priests convicted of sexual abuse.
But one of the commission's original members, Marie Collins of Ireland, said on Twitter this could hurt its independence.
While the Secretariat of State kept its premier position as administrative, coordinating and diplomatic department, the centuries-old high status of the doctrinal office was placed below that of the department of evangelisation.
The pope will head the evangelisation office himself, highlighting the importance he gives to spreading and reviving the faith.
Francis has already named a number of lay people, among them women, to Vatican departments.
Last year, he for the first time named a woman to the number two position in the governorship of Vatican City, making Sister Raffaella Petrini the highest-ranking woman in the world's smallest state.
Also last year, he named Italian nun Sister Alessandra Smerilli to the interim position of secretary of the Vatican's development office, which deals with justice and peace issues.
In addition, Francis has named Nathalie Becquart, a French member of the Xaviere Missionary Sisters, as co-undersecretary of the Synod of Bishops, which prepares major meetings of world bishops held every few years.
- Reuters