At its 30th anniversary, the Maastricht Treaty remains a milestone in the history and practice of the European Union. This referring to the adhesion process, since the set of conditions that a country must accomplish have been settled and derived by the treaty, but also for the fact that now, after 20 years of entering in force, the Euro, the Union currency, has performed and faced different consecutive challenges, thus becoming observable concerning it effects and role, and as a consequence, its theoretical and practical validity.

But there is yet a vast area, in the center of Europe, that is still dragging on its calvary of adhesion, that of the Western Balkans. At this point, considering the processes that the countries of this area have been going through, by pursuing the adhesion path, the analysis of the dominating factors that have determined the trajectory of their EU membership, becomes essential.

The paper questions and analyses the validity of the Maastricht Treaty and subsequent criteria for the adhesion of the Western Balkan countries, as well as highlights on the ‘ad-hoc’ criteria and evaluations often applied during the process and their consequences in terms of the attitudes of the Balkan populations and their determination toward the EU and the Western Balkans adhesion.