High Quality Content by WIKIPEDIA articles! Administratively, Portugal is a unitary and decentralized State. Nonetheless, operationally, it is highly centralized system with administrative divisions organized into three tiers. The State is organized under the principles of subsidiarity, local government autonomy, and democratic decentralization of the public service. Although mainland Portugal has yet to implement a regional level tier, the autonomous regions of Madeira and the Azores have their own regional political and administrative statutes and self-governing institutions.