Catholic cardinals will gather inside the Vatican for their closed-door conclave to elect the next supreme pontiff following the death of Pope Francis.

Catholic cardinals are gathering at the Vatican to elect the successor to Pope Francis, who died on April 21. Voting will take place in the Sistine Chapel, with ballots continuing in succession until any candidate secures two-thirds of the available votes.

The papal conclave begins May 7. Here's how cardinals choose the next pope, what to expect and how secretive the process is.