During the days of the East-West conflict, international institutions and organisations were part of international life, whether as intra-bloc institutions (WFO, COMECON, NATO, EC etc.) or as global or all-European ones (UN, CSCE). With the fundamental ideological and political divide gone the question arises: are there new prospects for fresh attempts to address the common problems and challenges by cooperation through international institutions? The old institutions must be transformed and adapted to the new requirements in order to realise the new opportunities for cooperative problem and conflict solving: in comparison with the past, institutionalised cooperation must incorporate new policy areas, competencies, instruments and decision-making procedures for a functional and politically adequate and effective handling of the institutions' list of tasks. This process of institutional adjustment in itself is a process of international bargaining. Asymmetries of concerns and the resulting differences of interests in a given policy area most likely go along with varying positions and preferences regarding institutional innovation. The articles of this volume address changes of international organisations which were in different ways directly linked to the East-West conflict, i. e. the United Nations, the CSCE, NATO and the EU. Which institutional adjustments have occurred within the various frameworks? Which institutional qualities have evolved, and what political significance can be expected by the institutions today or after the process of adjustment to the new international realities will have been more or less completed?