Today , industry is under constant pressure to increase competitiveness and resource-efficiency. One possibility to cope with these challenges is industrial symbiosis. Industrial symbiosis is based on substituting a new resource by an undervalued resource such as waste. Thereby , industrial symbiosis reduces waste and saves resources. One of the practical challenges in developing industrial symbioses is the identification of symbiosis opportunities. In particular , the question how " new resource – substitute " combinations can be identified has not yet been addressed in the literature. This paper presents a modeling approach for industrial symbioses in industrial parks , based on design structure matrices (DSM) , which intends to support the identification of substitution opportunities. The approach is applied to a sample industrial park. Combined with an optimization algorithm , the symbiosis model is used for identifying not only symbiosis opportunities but also the most attractive combination (s) of symbioses within the industrial park .