Among the College of Bishops, it has been a longstanding tradition of the Church, to raise certain bishops and archbishops to the College of Cardinals. The Cardinals have traditionally been seen as the "Princes of the Church". Because of their special devotion and holiness, they are called to assist the Holy Father in the governance of the Church. Most Cardinals are either Archbishops of the largest dioceses in their countries or regions, or the heads of the dicasteries of the Roman Curia (the Pope's Ministers of State, if you like).
Of course, the singular role that the Cardinals play is that of electing a new Pontiff when the See of Peter is vacant (see Electing a Pope). To them belongs this honour and responsibility.
Because the Cardinals are called to help the Pope in his leadership of the Church, they are also linked in a special way to the Diocese of Rome. A small number of Cardinals are made the titular bishops (ie, in name only) of the suburbicarian sees surrounding Rome. In addition, each of the remaining Cardinals is given the honorary "governance" of one of the Parish Churches of Rome. Whenever they visit Rome, they are encouraged to minister to their community in Rome. Strictly speaking, it is the Cardinal who is the "parish priest" of these parishes, not the priest who fulfils that role in reality. However, in real terms, the Cardinal's position in that church is only titular.
There are three degrees within the College of Cardinals:
This does not correspond to their actual degree of orders (ie, whether they are a bishop, priest or deacon) but to their position within the College of Cardinals. Cardinals appointed from dioceses around the world are made Cardinal Priests. Cardinals appointed from within the Roman Curia are made Cardinal Deacons. However, after having been a Cardinal Deacon for 10 years, the Cardinal can petition the Pope to be promoted to Cardinal Priest. The distinction between the three degrees of Cardinals has little practical significance except in determining the order and rank for ceremonial processions. Also, during the period after a Pope dies and before a new one is elected, it is one's position within the College of Cardinals that determines one's power to exercise certain powers if the Dean of the College of Cardinals or Camerlengo are unable to do so.
Pope John Paul II most recently appointed new Cardinals to the College in 2003 when he created 42 new cardinals, including two that he had been reserving "in pectore" from a previous Consistory. This means that they were appointed, but only he knows who they were (usually to protect the cardinal in question where they find themselves living in a situation of persecution, eg, in China). If the Pope had died before their names were revealed, they would not have been able to claim their "red hat". They do not have the right to vote in Conclave while their names have not been revealed, but once revealed, their seniority in the College dates from the date they were named "in pectore" not from the date their names were revealed.
This was Pope John Paul's ninth ordinary public consistory for the naming of cardinals. In the previous six consistories, he created 137 cardinals. The previous consistories were held on: June 30, 1979 (15 cardinals, of whom one was "in pectore"); February 2, 1983 (18); May 25, 1985 (28); June 28, 1988 (24: he had named 25 but theologian Hans Urs von Balthasar died on June 26); June 28, 1991 (22); November 26, 1994 (30); 18 February 1998 (20) and 2001 (44).
Pope Paul VI's Apostolic Constitution "Romano Pontifici Eligendo," promulgated on October 1, 1975, established numerical limits for the College of Cardinals. It stated that cardinals who had reached the age of 80 could not enter into conclave, and that the number of electors could not go beyond 120. Pope John Paul II continued this limitation when he revoked "Romano Pontifici Eligendo" and introduced a new revised set of rules for papal elections in "Universi Dominici Gregis" in 1996. However, in the 2001 Consistory and again in 2003, the Holy Father ignored the limit he had set and appointed a large number of Cardinals, taking the number of Cardinals under 80 (and therefore eligible to vote) to 137.
Click here for a list of the current Cardinals.