The notion of region is particularly vague, as this issue is referred to by studies from various disciplines. It has long been one of the subjects of interest of the Council of Europe which perceives local and regional administration as one of the fundamental ingredients of modern European democracy. The European Charter of Local Self- -Government is the main document that regulates these matters in the Council of Europe law system. It is accompanied by a number of other documents, including The European Charter of Regional Self-Government. The article provides an analysis of these normative deeds within the realm of Union law. When the Single European Act entered into force, regions have become an important part of Union policy. Committee of the Regions set up in 1994, whose operation is related to the principle of subsidiarity and programming of the idea of the Europe of Regions, is the most important body concerned with regional issues.