How New Popes Are Chosen: Secrets of the Conclave, Explained

For centuries, the head of the Roman Catholic Church has been chosen through what’s known as a papal conclave. The proceedings are cloaked in secrecy, making them the subject of speculation and intrigue.

On Wednesday, 133 senior members of the clergy, known as cardinals, will head into the Vatican’s Sistine Chapel to cast ballots. They aren’t allowed to leave or communicate with the outside world until they’ve reached an agreement. The process can last days, weeks, sometimes years.