Regional Development Dialogue, Vol. X, No. 2, Autumn XXXX CROSSROADS BETWEEN RESOURCE RECOVERY AND INDUSTRIAL SYMBIOSIS NETWORKS Evidences from Case Studies I. Costa and P. Ferrão INTRODUCTION Waste management policies are based in two fundamental principles: 1) to reduce waste generation, and; 2) to reduce the impact associated to waste production or, even better, to make waste useful as a new material. In this context, moving from linear to circular material and energy flows is considered as a general guideline to promote sustainability, although the environmental benefits of this operation require a careful analysis by making use of tools such as life cycle assessment. The objective is to achieve ever- increasing levels of reliance on waste material (recycling of matter) and energy recycling (cascading of energy) and on renewable materials and energy resources, i.e. to adapt the industrial (sub) systems to the (mother) ecosystem 1/ . In this context, there are two main approaches: industrial symbiosis and resource recovery. Industrial symbiosis generally implies a self-organizing business strategy among firms that are willing to cooperate to improve their economic and environmental performance, by exchanging waste and by-product materials or energy and using them in substitution of a primary resource. This is a form of synergy, understood as a collaborative interplay between entities towards accomplishing a result, which is more beneficial than what they could achieve by acting alone. In the context of IS, industries collaborate in exploring their own resource inefficiencies, resulting in an overall environmental and economical improvement of network performance. Resource recovery networks involve companies whose main industrial activities are recovering recyclable materials from waste flows, disassembling products into their material components, remanufacturing or recycling (e.g. plastic waste to plastic pellets). Quite often such companies are embedded in national waste management networks, involving collectors, sorters, recyclers, and treatment facilities (e.g. incineration and landfill). According to the EU Directive on Waste 2/ , ‘recovery’ means any operation the principal result of which is waste serving a useful purpose by replacing other materials which would otherwise have been used to fulfil a particular function, or waste being prepared to fulfil that function, in the plant or in the wider economy. Likewise, ‘recycling’ means any recovery operation by which waste materials are reprocessed into products, materials or substances whether for the original or other purposes. Both definitions can be used either in the context of RR or IS networks: for the former, the main objective is to remove recyclable or reusable materials from the waste flow and reprocess them into secondary raw materials, while for the later, a manufacturer uses the