Abstract: The integration of EMIS and ERP-systems has been recognized as an important step towards a holistic and long-term oriented environmental management. A number of research projects attempted to model the environmental impact of products in ERP systems and to integrate environmental impacts into the operational decisionmaking and communication of companies with their customers. In this paper we elaborate further on a reference architecture that allows an increasing level of automation when calculating a company's environmental impact by concentrating on the own operations and assuming that the environmental impact data for input materials is provided by suppliers as a service.