The cardinals are soon to be locked inside the Sistine Chapel and told to pick the right man to lead the Roman Catholic Church.
They're there because Pope Benedict XVI shocked the world by becoming the first pontiff for 600 years to quit.
Pope Benedict stepped down in February
But should we care who's in charge when the white smoke emerges? We've listed the reasons why you should, and why you shouldn't, below. Let us know if they managed to change your mind in the comments section below.
Why you should care:
1) The new pope will be able to influence the thinking of 1.2 billion people around the world, including a fast-growing African following, who will look to him for guidance.
2) He can change the world. Pope John Paul II, who held the post from 1978 until 2005, is credited with a important role in bringing the Soviet regime to an end. They even tried to kill him.
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3) The next pontiff will shape the future of the church, for better or worse, with no imminent end to the historic sexual abuse scandal and corruption claims against the Vatican.
4) The direction he takes on issues like contraception, abortion and gay rights will have a direct impact on the lives of billions of people. A truly modernising pope would have a profound effect on huge parts of the world.
5) The Vatican is vital for the tourist industry - and the Italian economy needs all the help it can get right now.
The world waits for the white smoke
Why you shouldn't:
1) Whoever is elected has little chance of reforming the ancient institution, whose purpose is not to help the 1.2 billion Catholics is proclaims to lead, but to maintain its power, position and wealth in the temporal world.
2) The Papacy, like all religion, is based on an outright lie, and the human species would be far better served were it to turn to science and reason rather bronze age myths and superstition.
3) The Catholic Church is responsible for the cover up of the rape and torture of children in countries around the world. Would a new pope throw open the doors of the Vatican to help bring paedophiles to justice, or would he remain complicit in protecting offenders from justice? Clearly, the latter.
4) The Catholic Church is a prejudiced institution, preventing half the human race (women) from serving at a senior level within its ranks. Is a new pope likely to change this?
5) Since the resignation of Benedict XVI, being pope is no longer a job for life, so the cardinals can just pick another one if they get it wrong.