The EU enlargement process is a work-in-progress topic and a difficult puzzle to be solved. But what the article tries to propose is a simplified model that builds upon answering two main questions, the why and when enlargement occurs. Considering the Western Balkans case, I argue that the rational incentives of economic interest and reducing negative externalities of non-enlarging as well as constructivist/sociological incentives are by no doubt an important factor in the process of enlargement on both, demand and supply side.
Taken alone, they may only open the way to accession and reinforce different forms of institutionalization between the two parties. Still, this is not sufficient enough to finalize the enlargement process. In order to complete the process, adjustments at both (demand and supply) sides are needed. The applicant states have to adjust to (comply with) EU requirements while EU itself has to adjust (transform) its institutions to be capable of functioning when the new countries will be accepted.
Otherwise, if the candidate countries do not accomplish (at least) the Copenhagen criteria (a necessary condition) and if the EU is not being ready to accept new countries (capacity and integration issue) the enlargement process will be postponed until both conditions (sufficient condition) are fulfilled.
European Journal of Economic and Political Studies 2(1): 61-77
Dorian Jano, (2009)