Following the implementation on 1 September 2019 of the Kleisthenis I Programme, the administrative divisions of Greece consist of two main levels: the regions and the municipalities.

The first level of administrative division is composed of the new decentralized administrations (αποκεντρωμένες διοικήσεις, apokentroménes dioikíseis), comprising two or three regions (except for Attica and Crete), run by a government-appointed general secretary, assisted by an advisory council drawn from the regional governors and the representatives of the municipalities.

Mount Athos (self-governing, excluded from the Kallikratis Plan) The second level is composed of the regions (περιφέρειες, periféreies; sing.

δήμος, dímos), which have resulted from merging several former municipalities and communities (themselves the subject of a previous reform with the 1997 Kapodistrias plan).

They are run by a mayor (δήμαρχος, dímarchos) and a municipal council (δημοτικό συμβούλιο, dimotikó symvoúlio), elected every 4 years.