Article 137 of the Spanish Constitution establishes that the State is organized territorially in municipalities, in provinces and in the Autonomous Communities that are constituted; adding that all these entities enjoy autonomy for the management of their respective interests. In the area of local entities, the Constitution gives special importance to municipalities, guaranteeing their autonomy in Article 140, while establishing that their government corresponds to their respective municipalities.

Based on this prevalence of the municipality, article 141 provides for the existence of other local entities that are configured as groupings of municipalities, which are the Province and the Island, as well as others that can be created.

The basic regulatory regulations of the Entities that constitute the Local Administration are contained in Law /1985, of April 2, Regulating the Bases of the Local Administration. This regulation regulates the local government institutions and the competences that correspond to them.

In addition, in the development of this Law, the Autonomous Communities have approved their respective laws that develop the basic regulations, for which account is taken, above all, of the peculiarities of their territory and the distribution of the population in each Autonomous Community.

Likewise, the different sectoral laws often have provisions and references to the powers of local entities, so they must also be taken into account to know exactly the local competences in each Autonomous Community and in each sector of activity.

The local entities currently existing in Spain are as follows.

• The Municipality. They are 8,117 and constitute the basic entity of the territorial organization of the State and the immediate channels of citizen participation in public affairs.
• The Province. The Spanish territory has 50, although in the 7 uniprovincial Autonomous Communities their powers are assumed by the corresponding Autonomous Communities.
• The Island. In total there are 11, Illes Balears (4) and Canarias (7).
• Entities with a territorial scope lower than the municipality established or recognized by the Autonomous Communities. At present there are 3,719.
• The Comarcas or other entities that group several Municipalities, established by the Autonomous Communities. Currently there are 81, which are located in Catalonia (41), Aragon (32), Basque Country (7) and Castilla y León (1, El Bierzo).
• The Metropolitan Areas. There are 3, located in Catalonia (1) and Valencian Community (2).
• The Communes of Municipalities. Currently, there are 1,018 municipalities, which affect 6,190 municipalities, or 76% of the total.

Finally, the attention of the services provided by local entities requires financial resources that are periodically reviewed and that have been made effective through the successive regulatory reforms of the Law on Local Haciendas. These reforms have meant different modifications and adaptations to a changing reality and have been approved as local entities have new responsibilities and must meet new public services and citizen demands.