5 PREFACE The contributions in this special issue reflect upon the results of the European Union’s COST Action IS0601 (2007-2011) called CRIPO (Comparative Research into Current Trends in Public Sector Organization), which was led by the prominent public administration scholars Geert Bouckaert, Per Lægreid and Koen Verhoest. The main objective of the CRIPO project was to increase knowledge about current trends in public sector organization in Europe in order to contribute to theoretical knowledge and optimize methodologies, and thus to inspire sound and policy-relevant research conclusions. The CRIPO project brought together scholars on a European platform for comparative and longitudinal research, which led to empirical, theoretical and methodological advancements in the field. Ultimately 23 European countries and 95 individual researchers cooperated in a research network organized around several topics, such as population and proliferation of public sector organizations, autonomy, steering and control, performance, accountability and coordination of public sector agencies. From Central and Eastern Europe (CEE), Croatia, Estonia, Hungary, Lithuania, Romania and Slovakia participated actively in the project. While the agencification process in Western democracies has attracted enormous scholarly interest in the last two decades, similar trends in CEE countries have received very little attention so far. In addition, an overwhelming majority of existing public administration research in CEE consists of single-country case studies only. It can even be said that a tradition of comparative studies is missing in public administration scholarship in CEE. In this general context, the international network of researchers has provided a much needed framework for, first of all, starting systematic studies of agencification and, secondly, for carrying out empirical studies based on a common methodology, thus enabling comparisons both within CEE and beyond this region. The CRIPO network was international in its membership, dynamic in its search for comparability and pro-active in searching for combined methods of research, which allowed comparisons across countries, policy fields and time. The contributions in this special issue are based on various methods used within the CRIPO project. Whereas a few CEE countries (Lithuania and Romania) can rely on the results of the so-called COBRA questionnaire (“Comparative Public Organization Data Base for Research and Analysis”) initiated at the Katholieke Universiteit Leuven, the other country studies have built their empirical research on joint protocols for dynamic, longitudinal mapping of state administrations or on case studies developed within the CRIPO network. 6 Since in the majority of CEE states research on public sector organizations is less advanced than in most Western European countries, the contributions in this issue involve a strong descriptive element outlining the agency landscape and its evolution in each particular country. In addition, the authors were able to choose specific sub- themes that have influenced the design of public sector organization and reforms in their respective countries. On one hand, the novelty of such research in CEE has led to a replication of methodologies that have been used in Western countries within the past decades, by that allowing for cross-country comparisons. On the other hand, the CEE country studies have contributed to the existing knowledge of the field, for example, in studying the impact of the European Union and of the economic crisis on the (de)agencification process. This special issue features nine original articles. The introductory paper is written by B. Guy Peters of the University of Pittsburgh, who, in addition to being one of the co-founders of the COBRA network, has demonstrated keen interest in public administration reforms in CEE for more than a decade. Sandra van Thiel of the Erasmus University Rotterdam offers an important contribution by placing the agencification process in CEE countries in a broader international context, which allows it to identify “a CEE trajectory” of agencification. This is followed by six country studies on (semi-) autonomous agencies and other public sector organizations discussing developments in Croatia, Estonia, Hungary, Lithuania, Romania and Slovakia, and a summary article by the guest editors of this special issue focusing on the similarities and differences in the agencification process among the CEE countries. The aim of this special issue is not only to contribute to the academic studies of public sector organization but also to be relevant for policy-makers and agency practitioners. As most CEE countries are going through reforms in their public sector organizations, we hope that empirical evidence as well as the approaches, analytical frameworks and conclusions presented in this issue will be useful in designing, implementing and understanding public sector reforms. Guest editors of the special issue, Tiina Randma-Liiv, Vitalis Nakrošis and HAJNAL György