This thesis examines the impact of European Structural Funds’ Regulations on the administrative arrangements regarding regional policy process in Greece. More specifically, it examines to what extent the application of the Regional Development Fund during the two programming periods 1989-1993 and 1994-1999, has initiated changes in the administrative structures of the country, as well as changes in the logic of regional policy formulation and implementation. The presence of the literature on Europeanisation of domestic administrations, conceived as administrative adaptation to European Regulations’ requirements, is followed by a discussion of the 1988 reform of the European Structural Funds and the principles introduced or re-enforced in this context. An analysis of the political and administrative culture of Greece, as well as a description of the State organisation is offered. Subsequently the national regional policy process is discussed, with view to highlighting the situation prevailing in regional policy process preceding the 1988 reform and its application. After a presentation of the main theoretical approaches to Europeanisation, the institutionalist approach is studied, as the most appropriate to interpret the response of the Greek administrative system to the requirements of the Structural Funds’ Regulations. The specific reasons why institutionalism is deemed as the proper analytical tool in the case of Greece are analysed. The empirical research involves initially the discussion of the administrative reforms introduced in response of the Structural Funds Regulations at the national level. Apart from the legal changes, the reaction of the central administration and the experience of central government actors regarding the process of the reforms are reported. The case study focuses on the Region of Thessaly, and discusses the Regional Operational Programmes corresponding to the two programming periods. It highlights the clash between the principles of the European Regulators on the one hand, and domestic practices on the other, confirming the findings reported at the national level. The loci of resistance to change are traced, in a way that brings into relief the role of culture in forging patterns of action and interaction in public policy process. Finally, the theoretical and empirical parts are brought together in a conclusive manner.