Greek foreign policy towards the Balkans in the post-Cold War era had two phases. First phase was characterised by the de-Europeanisation as opposed to the significant process of Europeanisation in 1970s as hysterical nationalism and irrational, aggressive expressions whereas the second phase was the adequate manifestation of re-Europeanisation as decreasing nationalism, rational redefinition of national interests and of possessed assets, and successful use of economic relations. The relations with Bulgaria have been often smooth although they suffered initially because of irrational Greek reactions to the Bulgarian recognition of Macedonia and BulgarianTurkish rapprochement. The relations between the two countries were further deepened during the second phase of Greek foreign policy. In any case, the then unique identity of Greece as a Balkan country in the EU has been manifest in its foreign policy towards the Balkans. The reEuropeanisation of Greek foreign policy contributed significantly to regional stability. One would like to regard this Europeanisation as immutable yet many core issues remain unsolved. The process of the solution of those core issues will show whether Greek foreign policy vacillates in the cycles of Europeanisation and de-Europeanisation or not. This implies that the Europeanisation process is neither immutable nor irreversible