This article opens briefly with the recent discussions about the effectiveness of pollution prevention. As pollution prevention and cleaner production are important elements of industrial ecology, the different definitions and approaches of industrial ecology as a term also need clarity. The major part of this article reflects the first results of the cleaner production and industrial ecology concepts, applied in an industrial ecosystem project (INES) in the Rotterdam harbour area. In this industrial area with many refineries and (petro) chemical facilities, the possibilities for companies to reuse waste streams, by-products and energy from each other was researched. The project was initiated by an industrial association. Sixty-nine members of the industrial association joined the INES project and provided confidential information about their resources, products and waste streams to the research team. Based on this information, 15 projects were designed. The selected three projects for further feasibility studies showed the potency to reduce the use of energy, water and bio sludge significantly. http://www.sciencedirect.com/science/article/pii/S0959652698000158