As Pope Francis continues to fight double pneumonia in hospital, many have begun to wonder what the process would be if he were to step down on health grounds like his predecessor, Pope Benedict XVI.The method the Catholic Church uses to select their leader has remained virtually unchanged for the last 800 years.

Concerns over Pope Francis' health have mounted in recent years as have questions about his succession. Here's what we know.

Images of Pope Francis are seen outside Gemelli Hospital, where Pope Francis is admitted for treatment, in Rome, Italy, February 26, 2025. REUTERS/Hannah McKay