Industrial symbiosis (IS) continues to raise the interest of researchers and practitioners alike. Individual and haphazard attempts to increase linkages among co-located firms have been complemented by concerted efforts to stimulate the development of industrial regions with intensified resource exchanges that reduce environmental impact. Additionally, there are examples of both spontaneous and facilitated linkages between two or more firms involving flows of materials/energy waste. A striking feature of IS activities is that they are found across diverse social contexts and vary considerably in form (Lombardi et al., 2012); there are substantial differences in the ways in which IS manifests itself. Equally diverse are the activities of policy makers to stimulate such linkages. Such diversity can already be found within Europe, as became apparent in a first meeting among some of the present authors in 2009 (Isenmann and Chernykh, 2009). Researchers present there decided to create a network of European researchers on IS, with the explicit aim to develop a comparative analysis. We can thus provide insight to the relationship between the style of IS and its context and thereby the potential for policy makers in different contexts to learn from each other. Policy learning can be a tempting route to IS, but is fraught with difficulties if the influence of context is not appreciated (e.g., Wang et al., Chapter 6, this volume).