In Christianity, the doctrine of Apostolic Succession (or the belief that the Church is 'apostolic') maintains that the Christian Church today is the spiritual successor to the original body of believers in Christ, composed of the Apostles. Different Christian denominations interpret this doctrine in different ways.
In episcopal churches, the Apostolic Succession is understood to be the basis of the authority of bishops (the episcopate). In the Roman Catholic Church and the Eastern Orthodox Church, Apostolic Succession is claimed as having been passed through unbroken lines of bishops beginning with the original Apostles. The Catholic Church has traditionally been the most vocal in claiming unique legitimacy in terms of Apostolic Succession based on the assertion that Saint Peter, believed to be the rightful leader of the Church, was the first Bishop of Rome. Other communions such as Anglicanism and Oriental Orthodoxy claim legitimacy on a similar basis. Virtually all Christian denominations consider Apostolic Succession important in some fashion, although their definitions of the concept may vary.