Cross-Border Cooperation between territorial communities or authorities is a constant priority for the Council of Europe.
In 1980 the Council defined the legal framework for Cross-Border Cooperation in the Madrid Convention, a document on transfrontier co-operation between territorial communities or authorities developed within the European Outline Convention. The Madrid Convention was followed by three protocols adopted on 9 November 1995, 5 May 1998 and 19 November 2009