White smoke will soon rise again from the Sistine Chapel chimney, signaling a new era of leadership in the Catholic Church — but first, there must be prayers, meetings and a highly secretive conclave.

Francis’ successor will be selected by cardinals at the conclave that begins on May 7. Cardinals, known as the “princes of the church,” rank just below the pope in the Roman Catholic Church; together, they are known as the College of Cardinals. When a pope dies, the college chooses a successor.