The countries of the Western Balkans, candidates for membership of the European Union (EU), face multiple challenges. One of these challenges, the subject of this paper, is caused by the authoritarian trends in Serbia and Montenegro. There is a major risk of the emergence of an “illiberal” bloc in South-East Europe. The evolution of the countries’ incumbent regimes raises questions around their commitment to the EU’s values. The most urgent issues include patronage at the highest levels of the state, press freedom and, to a lesser extent, in Serbia’s case, the role of the intelligence services. This paper concludes that it is necessary to relaunch the debate over EU enlargement to the Western Balkans.