Roman Catholic cardinals from around the world have gathered in Rome to begin the process of electing the next Pope.
Cardinals held prayers and swore oaths of secrecy at their first meeting, held by the College of Cardinals.
There will be a series of daily meetings leading up to a conclave, expected to begin next week, in which a new Pope will be chosen.
The election process comes after Pope Benedict XVI stepped down last week.
He was the first pontiff to resign in 600 years, after nearly eight years in office leading the world’s 1.2 billion Roman Catholics.
The first pre-conclave meeting on Monday morning was headed by the dean of the College of Cardinals, Cardinal Angelo Sodano.
The Vatican said 101 of the 115 cardinals involved in the conclave have arrived in Rome. A further 12 are due to arrive either today or tomorrow, while two are not attending.
They are the UK’s Cardinal Keith O’Brien, who is standing down amid allegations of improper behaviour, and Indonesia’s Julius Darmaatmadja, who is ill.
At the pre-conclave meetings, cardinals – known as the “princes” of the Church – will discuss future challenges and discreetly weigh up possible papal candidates.
The conclave – to be held in the Sistine Chapel – is expected to take place next week, though the exact date will be agreed on in the coming days.
Correspondents say the cardinal electors, those under the age of 80 who will take part in the conclave, will want the new Pope to be officially installed in time to preside over Holy Week.
Ceremonies start with Palm Sunday on 24 March and culminate in Easter the following Sunday.
Last year’s “Vatileaks” scandal is expected to be high on the agenda during the meetings.
Corruption and infighting in the Vatican were exposed through a series of leaked documents, and the cardinals are expected this week to be briefed on a confidential report into the scandal seen by Pope Benedict.
The BBC’s David Willey in Rome says strict precautions against leaks of unauthorised information will be in operation at the Vatican until the next Pope has been chosen.
Technicians will debug the cardinals’ lodgings and mobile phones will be banned altogether during the conclave.
But some cardinals have suggested the internal workings and possible failings of the Vatican’s bureaucracy will not be a major factor in the decision to elect the next pope.
“I think the real priority in the conclave is to choose the pope who is going to deal with these great, global issues,” said Cardinal Donald Wuerl of Washington, speaking to the Associated Press in Rome, before the meetings began.
“If there are some internal problems in the Vatican, administrative problems in the Vatican, that’ll eventually be dealt with. But it certainly isn’t going to condition how I am going to be looking at who is going to guide and lead the church in the next years.”
The church’s handling of allegations of sexual abuse is another recurring issue.
Cardinal Keith O’Brien, formerly Britain’s former most senior Roman Catholic cleric, has said he will not take part in the conclave after standing down amid allegations of improper behaviour.
On Sunday, he admitted his sexual conduct had at times “fallen beneath the standards expected of me”.
He apologised and asked forgiveness from those whom he had “offended”.
Cardinal O’Brien resigned as Archbishop of St Andrews and Edinburgh last Monday after three priests and a former priest made allegations against him dating back to the 1980s.
Benedict, 85, officially ceased to be the Pope at 20:00 local time (19:00 GMT) on Thursday.
He left the Vatican by helicopter, flying to the papal retreat at Castel Gandolfo, near Rome.
He has vowed “unconditional obedience and reverence” to his successor.
The German pontiff, who was born Joseph Ratzinger, will continue to be known as Benedict XVI, with the new title of “pope emeritus”.
The theologian is expected to retire to a monastery on a hill inside Vatican City. Officials say he will not be able to intervene publicly in the next papacy although he may offer advice.