This article focuses on how domestic and EU-level political factors affect the functional aspect of the national coordination of EU affairs. Due to the idiosyncrasies of the post-communist countries which have joined the EU since 2004, an analysis of dynamic changes in the national systems of coordination needs to focus on three factors: (a) functional pressures from the EU; (b) the consolidation of the national party system; and (c) existing traditions of politico-administrative relations. The international economic and financial crisis is considered as a fourth factor that has affected the first three factors through the increase in the EU's 'informal intergovernmentalism', which adds to the politicization of EU matters. The Slovenian case points to an increased, though selective, politicization of EU business due to both national- and EU-level factors.