The project?s main focus will be to analyse how consulting engineering companies manage relevant flows of knowledge with respect to environmental issues. More specifically, we will use the concepts from science and technology studies to pursue the followi ng six set of research issues: 1. Learning and knowledge acquisition, 2. Activities of mediation, 3. Calculation and representation efforts with respect to sustainability, 4. Knowledge management activities in the company and its relevance for ?greening? their services, 5. How environmentally oriented consulting engineering services are commercialised; options and challenges, and 6. Practices of interdisciplinarity and new combinations of knowledge with respect to environmental issues. Thus, the main co ntribution from the project will be twofold. First, we aim to contribute to the international research literature on boundary organisations but above all to improve the knowledge about the epistemic culture of consulting engineers and the relationship bet ween (consulting) engineering and environmental knowledge. This implies also to contribute to the scientific understanding of interdisciplinary knowledge practices with respect to sustainability. Second, we will supply new and rich descriptions and analys is of the management of environmental knowledge in Norwegian consulting enterprises, how this is viewed by users, and the shaping of the industry that offers knowledge-intensive services to serve environmentally oriented decision-making. Taken together, t his will represent what we believe will be an important scientific contribution to environmental studies as well as a point of departure to improve practices in the consulting engineering industry and policy-making with respect to this industry.