"A diocese is a portion of the people of God which is entrusted to a bishop for him to shepherd with the cooperation of the presbyterium, so that, adhering to its pastor and gathered by him in the Holy Spirit through the Gospel and the Eucharist, it constitutes a particular church in which the one, holy, catholic, and apostolic Church of Christ is truly present and operative."
(Code of Canon Law, can. 369)
"'Particular Church,' which is the diocese (or eparchy), refers to a community of the Christian faithful in communion of faith and sacraments with their bishop ordained in apostolic succession."
(Catechism of the Catholic Church, 833)
In the Czech Republic, there are 2 ecclesiastical provinces with 8 dioceses and an Apostolic Exarchate.
The Province of Bohemia consists of:
The Province of Moravia consists of: