Recent European Union (EU) directives in the environmental field have promoted sustainable development alongside new modes of environmental governance for achieving this elusive goal. These modes are characterised by integrated, participatory and transparent decision-making processes. This paper provides a conceptual clarification of this new environmental governance and then examines the extent to which it is being promoted, through Europeanization, in one of the impending south-eastern enlargement countries, Turkey. Empirical data is taken from an analysis of Turkey's progress in adopting the Strategic Environmental Assessment Directive which – potentially at least – embodies features of the new environmental governance. A key finding is that there are close links between the adoption of the new modes of environmental governance and the power of ‘Europeanization discourses’ in national policy making processes, but these are insufficient to forge significant changes in inter-sectoral working around environmental issues, or markedly expand opportunities for public participation. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.