A Consistory is a formal meeting
of the College of Cardinals convoked and presided over by the
Supreme Pontiff. It can be Ordinary or Extraordinary.
An Ordinary Consistory is when
the cardinals, at least all those present in the city of Rome, are
called together ... to be consulted on certain serious matters
which nevertheless occur rather frequently, or to carry out
certain very solemn acts" (CCC canon 353, §2).
An Extraordinary Consistory is
when "(A)ll the cardinals are called together ... when the
special needs of the Church or the conducting of more serious
affairs suggests that it should be held" (CCC canon 353,