<P> Ordination to the episcopate is the fullness of the priesthood and the completion of the sacrament of Holy Orders . Bishops are considered the successors of the apostles . </P> <P> Within the Catholic Church the following posts have similarities to that of a diocesan bishop, but are not necessarily held by a bishop . </P> <P> Canon 368 of the Code of Canon Law lists five Latin Church jurisdictional areas that are considered equivalent to a diocese . These are headed by: </P> <Ul> <Li> A Territorial Prelate, formerly called a Prelate nullius dioceseos (of no diocese), in charge of a geographical area that has not yet been raised to the level of diocese </Li> <Li> A Territorial Abbot, in charge of an area, which in mission countries can be quite vast, associated with an abbey </Li> <Li> A Vicar Apostolic (normally a bishop of a titular see), in charge of an apostolic vicariate, usually in a mission country, not yet ready to be made a diocese </Li> <Li> A Prefect Apostolic (usually not a bishop), in charge of an apostolic prefecture, not yet ready to be made an apostolic vicariate </Li> <Li> A Permanent Apostolic Administrator, in charge of a geographical area that for serious reasons cannot be made a diocese . </Li> </Ul>

What do you call the head of a catholic church