The similarly titled episcopal vicar shares in the bishop's ordinary executive power like the vicar general, except for the fact that the episcopal vicars' authority normally extends over only a particular geographic section of a diocese or over certain specific matters. These might include issues concerning religious orders or the faithful of a different rite. These too must be priests or auxiliary bishops. The equivalent officer in the Eastern Churches is called the syncellus.
Priests appointed as vicars general or episcopal vicars are freely appointed or removed by the diocesan bishop, and must be appointed for a fixed duration. They lose their office when the term expires, or when the episcopal see falls vacant. Auxiliary bishops may also be removed from the office of vicar general, but must at least be appointed episcopal vicar. An auxiliary bishop who is an episcopal vicar, or a coadjutor bishop who is vicar general, may only be removed from office for a grave reason. Likewise, while they lose their vicar general or episcopal vicar office sede vacante, they retain the powers of the office until the succeeding bishop takes over the diocese. A coadjutor bishop has right of succession as coadjutor, so if the see falls vacant he becomes the diocesan bishop immediately.
The appointment of a vicar general is also a useful tool for a diocesan bishop who has additional functions attached to his episcopate. The most notable example is what occurs in the diocese of Rome. The Pope is the diocesan bishop of Rome, but since he must spend most of his time governing the Latin Church and the global Catholic Church, his vicar general functions as the de facto bishop of the diocese. The Vicar General of Rome also serves the same role for the suburbicarian diocese of Ostia, the traditional see of the Dean of the College of Cardinals, since it was merged with the diocese of Rome. The Vicar General of Rome, who is normally a cardinal, known as the Cardinal Vicar, is one of the few church officials in Rome to remain in office sede vacante. The current Vicar General of Rome is Cardinal Camillo Ruini.
A similar example is found in the United States, where the archbishop of New York functioned also as ordinary of the military services from World War I until the 1980s: in addition to being responsible for the archdiocese of New York, that same archbishop was also responsible for the Military Ordinariate, which had the status of an apostolic vicariate, and functioned as the equivalent of a diocese defined by quality (that is, all Catholic members of the U.S. military and their dependents) rather than by geography. The archbishop had two separate administrations, therefore, and two sets of vicars general to manage each. This arrangement ended with the establishment of the wholly separate Archdiocese of the Military Services.
Following the Act of Supremacy of 1534, Henry VIII appointed Thomas Cromwell as his vicar general, a delegation of the powers with which Henry was invested by the Act as a result of becoming supreme head of the Church of England.