The construction and development of the European administration represent also nowadays controversial topics, determining new paradigms which are situated at the interface between traditional and modern in the approach of the theory and science of administration. The current publication represents in its first part a relevant synthesis concerning the sphere and content of European administration, reform and its legitimacy as well as the theoretical pertinence of the models aiming its description. The processes of European integration, Europeanization, administrative convergence and dynamics are becoming emergent in view to create and strengthen both a unique organization, the European Union and an own administration, fundamentally different in relation to national administrations through complexity, openness and effectiveness. The second part achieves an empirical assessment of the level of internalization of the European Administrative Space principles in the public administration in Romania. The book addresses to specialists and practitioners in the field of public administration and European integration, opening new horizons of analysis for academia and research environment.