In recent years, the failure of models based on rules and procedures fostered the development of new paradigms of Public Management, which are still the object of a heated interdisciplinary discussion. A growing number of scholars have debated the role of performance measurement, transparency, and accountability in strengthening the link between public administration and citizens. Moreover, the belief that more trust and satisfaction could lead to better governance has persuaded a growing number of Nations to shift from a pure efficiency orientation to a more extensive customer-centered one. Anyway, the transition to a new management model is not problemless at any level of Public Administration and the cultural systems of public organizations seem to have an important role. The paper aims to define the conceptual frame of new paradigms of Public Administration, and to underline the difficulties and the peculiarities in accomplishing those models both at political, and operational level.