Cleaners and cooks. Doctors and nurses. Even drivers and elevator operators. The support staff for the cardinals who will elect the successor to Pope Francis took an oath of secrecy Monday ahead of the conclave that’s starting on Wednesday.

Cooks and cleaners as well as maintenance and medical staff joined members of the Vatican's clergy on Monday (May 5) to take an oath of secrecy ahead of the upcoming papal conclave. Could cells grow food for astronauts on long missions in space?

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.

Over 130 voting cardinals must decide whether to continue in the direction of Francis or elect a pope likely to choose a more traditional path.