Next in the Rankings: Cardinals

Since the Catholic Church has more than a billion members worldwide, there are many layers under the pope who keep the system working. The levels go like this: Pope-cardinals-archbishop/bishop, vicar generals, monsignors, and priests. The rest of the Church consists of deacons, monks, nuns, brothers, sisters, and laypeople. Even though they are at the bottom, laypeople consist of 99.9 percent of the Church.

Although their primary responsibility is to elect the pope, cardinals have many other administrative responsibilities as well. The Roman Curia is the entire group of administrators that head up departments working together as the right hand of the pope. The pope governs the Church through the Curia, much like a U.S. President uses his cabinet. For example, a Cardinal Secretary of State represents the Holy See to foreign governments, since the Vatican is an independent country. A cardinal also heads each congregation, such as the Congregation for Bishops or the Congregation for Catholic Education. Overall, other Congregations include: Causes of the Saints, Clergy, Divine Worship, Evangelization of Peoples, Institutes of Consecrated Life, and Oriental Churches.

A different cardinal heads up each of several councils and commissions, along with the three high courts of the Catholic Church: the Apostolic Penitentiary, the Apostolic Signaturia, and the Roman Rota, all of which deal with canon law and its application and interpretation.

Cardinals that don't work in the Curia will run an archdiocese, mostly functioning the way an archbishop would-ordaining, confirming, and running the day-to-day business of being head of an archdiocese. These cardinals are often the metropolitans, which means that they supervise a group of two or more dioceses. A metropolitan doesn't have immediate authority over a bishop in the diocese under him, even though he oversees the region.

A metropolitan reports to Rome, however, if one of the bishops in his province is derelict in his duty or some commits some other scandalous behavior. Often, the apostolic nuncio, the papal ambassador to a country, will consult with the cardinal when vacancies arise in his province as the result of a bishop retiring or dying. For example, the Archdiocese of Atlanta oversees the diocese of Charleston (consisting of all of South Carolina), along with other dioceses in Florida, Georgia, and North Carolina.