A personal prelature is made up of a particular group of faithful and is structured in a hierarchical manner, with a prelate who is its head and source of unity and with priests and deacons who assist him. Hence it is a part of the Catholic Church. The specific function of personal prelatures is to foster Christian life and the Church’s evangelizing mission in a way that complements the dioceses, to which the faithful who form part of a personal prelature continue to belong.
The role a personal prelature plays in complementing the dioceses can respond to various needs, always related to the spiritual good of the faithful. It might happen, for example, that the desire to encourage a greater participation of immigrants in ecclesial life leads to a prelature being organized with a clergy trained to attend to their specific needs. Or as is the case with the prelature of Opus Dei, an ecclesial reality that stems from a charism (that is, from a gift of God to the Church) might have the characteristics suited to a personal prelature.