When a pope dies or resigns, the governance of the CatholicChurch passes to the College of Cardinals. Cardinals are bishops and Vatican officials from all over the world, personally chosen by the pope, recognizeable by their distinctive red vestments. Their primary responsibility is to elect a new pope.

Following a vacancy in the papacy, the cardinals hold a series of meetings at the Vatican called general congregations. They discuss the needs and the challenges facing the Catholic Church globally. They will also prepare for the upcoming papal election, called a conclave. Decisions that only the pope can make, such as appointing a bishop or convening the Synod of Bishops, must wait till after the election. In the past, they made arrangements for the funeral and burial of the deceased pope.

Four rounds of balloting are taken every day until a candidate receives two-thirds of the vote.

In the past, 15 to 20 days after a papal vacancy, the cardinals gathered in St. Peter's Basilica for a Mass invoking the guidance of the Holy Spirit in electing a new pope. Only cardinals under the age of 80 are eligible to vote in a conclave. They are known as the cardinal electors, and their number is limited to 120. For the conclave itself, the cardinal electors process to the Sistine Chapel and take an oath of absolute secrecy before sealing the doors.

The cardinals vote by secret ballot, processing one by one up to Michelangelo's fresco of the Last Judgment, saying a prayer and dropping the twice-folded ballot in a large chalice. Four rounds of balloting are taken every day until a candidate receives two-thirds of the vote. The result of each ballot are counted aloud and recorded by three cardinals designated as recorders. If no one receives the necessary two-thirds of the vote, the ballots are burned in a stove near the chapel with a mixture of chemicals to produce black smoke.

When a cardinal receives the necessary two-thirds vote, the dean of the College of Cardinals asks him if he accepts his election. If he accepts, he chooses a papal name and is dressed in papal vestments before processing out to the balcony of St. Peter's Basilica. The ballots of the final round are burned with chemicals producing white smoke to signal to the world the election of a new pope.

The senior cardinal deacon, currently French Cardinal Jean-Louis Tauran, announces from the balcony of St. Peter's "Habemus Papam" ("We have a pope") before the new pope processes out and imparts his blessing on the city of Rome and the entire world.