The episcopate is the status of a bishop. In the Roman Catholic, Anglican (including what in the USA is called the Episcopal Church), Eastern Orthodox, Oriental Orthodox, and Assyrian/"Nestorian" churches, and in a few Protestant churches (but not in most), it is held that only a person in a line of succession of bishops dating back to the Apostles can be a Christian bishop, and only such a person can validly ordain Christian clergy. The succession must be transmitted from each bishop to a successor by the rite of Holy Orders. Bishops in such a succession compose the historic episcopate. This is also called the apostolic succession, but that term is also used in a variety of other ways.

The Roman Catholic Church holds that a bishop's consecration is valid if the sacrament of Holy Orders is validly done and the consecrating bishop's orders are valid, regardless of whether this takes place within or outside of the Catholic Church. Thus, Catholics recognize the validity of the episcopacy of Eastern Orthodox and Oriental Orthodox bishops. They do not recognize Anglican bishops, because of changes in the rite of Holy Orders in the Anglican churches.

The Eastern Orthodox Church holds that a bishop's consecration is less than fully valid if it is not within the "One Holy Catholic and Apostolic Church", i.e., one of the canonical Eastern Orthodox churches. In many cases, the doctrine of ekonomia is applied to such bishops if they convert to Orthodoxy.

See also: Episcopalian church governance