This article examines the potential impact of eastern enlargement on EU environmental governance. Whereas some observers see eastern enlargement as a potential threat to EU environmental governance, this contribution argues that it should be seen as an opportunity to intensify ongoing reform efforts.

This view is based on three main premises. First, enlargement is likely to have a differential effect on the three governance regimes which together constitute EU environmental policy. Second, the threat that enlargement poses to one of these regimes is in fact already producing reactions that may allow the regime to continue to operate in the context of an enlarged EU. Third, enlargement may reinforce emerging shifts among the regimes, which answer to the larger challenge of sustainable development.

Since the second half of the 1990s, post-communist transition processes in Central and Eastern Europe have become increasingly bound up with European integration. The wish of many CEE countries to join the EU and the conditions which the EU has formulated for accession have played an important role in shaping transition processes. Conversely, it has become increasingly clear in recent years that Eastern enlargement also poses a major challenge for the EU. Rather than focusing directly on environmental transition processes in CEE countries, the discussion primarily considers the potential impact of eastern enlargement on EU environmental governance. Two closely related considerations suggest that an understanding of this factor is a crucial pre-condition for analysing the future of environmental transition processes in CEE. First, EU environmental policy generally has a very strong, if not overriding influence on the environmental policies of EU Member States - a group of countries to which the accession countries will soon belong. Second, as a result of the accession process, EU environmental legislation already largely determines the environmental policies of the CEE countries.

The analysis proceeds in five parts. Against the background of relevant debates among policymakers and analysts, the first part presents the main hypotheses. The second part introduces the historical-institutionalist perspective on which the subsequent analysis draws. Part three identifies and describes three EU environmental governance regimes. This is followed by a discussion of the main features of environmental policy in the ten CEE accession countries. The last part discusses how enlargement could affect each of the three EU environmental governance regimes.