The evolution and development of institutions mean several changes with different intensities; either they adapt to the changes in the environment, either they exploit certain opportunities. In order to survive to the accelerated pace of change specific for the modern society, the public institutions should find new forms of organization, more flexible, aiming to respond to the new priorities or to improve their activity. Romania is facing a process of change, where all the economic, social, political, civic elements have recorded a new dynamics, attempting to adapt to the current conditions. The process of change in public administration gained new dimensions in the last years. Romania and Bulgaria joined the EU on January 1, 2007. During the accession process and also after integration, public institutions in Romanian and Bulgaria suffered a series of changes. The paper aims to analyze, the efficiency and effectiveness of organizational change of public institutions in the context of public administration reform, in general, and in particular the changes determined by Romania and Bulgaria integration in the European Union. Analyze of efficiency of this change is important because the measures taken by public institutions in Romania and Bulgaria are similar to those taken in the process of Europeanization of ministries across the EU.