Modernisation of the European Union or just another modifi cation? Such a dilemma appears regularly during all inter-governmental conferences, specially before and after approving another revision treaty for the European Union. To answer such a question, fi rst the essence and meaning of these terms has to be explained, and to do so, the best option is to refer to their etymology. And so, according to the PWN “Dictionary of Foreign Words”, ‘modification’ »latin modification = measuring« is a change, transformation, remake; a modifi ed object, while ‘modernisation’ »fr. moderne = modern« is making something modern or making something contemporary’. Therefore, modernisation shall mean a broader and deeper process, these are actions leading to radical transformations and changes as compared to modifi cation, which usually precedes modernisation. It may then be said that as far as the European Union is concerned, commencing from its origination by the Maastricht treaty of 7th February 1992 till the latest revision treaty, i.e. the Lisbon treaty which became eff ective on 1st December 2009, we only witnessed its successive (permanent) modifi cation, that is slow transformations which were generally named extension and enhancement processes. Today, after nearly twenty years of remakes and use, the European Union needs not only a radical overhaul but rather modernisation, meaning its update and adapting to contemporary times. Today, the European Union requires adaptation to challenges and requirements of the 21st century determined by acceleration and globalisation progressing within all spheres of life.