Independent Catholic churches are Christian groups, particularly small groups, led by bishops and identifying with Catholic tradition but not in communion with the Roman Catholic Church or with any other churches whose sacraments are recognized by the Roman Catholic Church, such as the Eastern Orthodox and Oriental Orthodox Churches. The term "independent Catholic" is not usually applied to the Church of England or to the other member-churches of the Anglican Communion. However, "independent Catholic" is customarily applied to churches that consider themselves to be "Old Catholic", including the Old Catholic churches that form the Union of Utrecht even though the Union of Utrecht churches are in communion with the Church of England and with the wider Anglican Communion, but the Union of Utrecht churches are not actual member-churches of the Anglican Communion). In the case of Continuing Anglican churches outside the Anglican Communion, churches identifying with Catholic tradition may sometimes be considered as being independent Catholic churches. Virtually all groups in the independent Catholic movement claim to have valid apostolic succession for their bishops. The bishops of independent Catholic churches are sometimes referred to as episcopi vagantes ("wandering bishops") because of their lack of affiliation with a larger communion of churches.