Regarding methodology development, a general framework of three elements is defined and elaborated: systems definition, inventory and modeling, and the interpretation of the results. Three possibilities are identified to model an SFA system, each with their own strong points and limitations. Accounting, i.e. keeping track of substance flows and stocks through the years by registering them, can be used as a monitoring tool. It enables one to spot trends and evaluate the effects of certain policies. Static modeling can be used to assess the origins of pollution problems in the economic system, and to estimate the effectiveness of intended policy measures. Dynamic modeling, the most elaborate and least developed of the three possibilities, can be used for forecasts and predictions. For the interpretation of the results, substance chain indicators are developed. Finally, a methodology is outlined to develop substance chain management strategies based on so-called economic substance characteristics. 

The SFA method is applied for two case studies: cadmium and nitrogen compounds in the European Union. For both, an account has been drawn up of the existing flows in, out and through the EU. The origins of established pollution problems are assessed, the effectiveness of the current EU policy as it is defined in various Directives has been estimated, and various alternative measures packages have been defined and calculated using static modeling, in order to point out the most promising directions for a management strategy. 

For a successful cadmium policy, the generally accepted notions of source-oriented policy and recycling appear to have to be amended. The EC policy, conforming to those notions, does not appear to offer a sustainable solution to the cadmium problem, mainly because it does not consider the inelastic nature of cadmium supply, that is, primarily as a by-product of zinc. In order to be effective, a cadmium policy must take into account the way Cd enters and filters through the economic system. The existing policies for nitrogen compounds are mostly of a technical, end-of-the-pipe nature. Provided adequate implementation, such technical problems may solve some of the N-related problems. However the problem of groundwater pollution will remain unresolved, even assuming very stringent technical measures. This is due to the inherent inefficiency of agricultural processes. A resolution of this problem to the degree laid down in the various agreements implies very drastic changes in agriculture and/or feeding habits of the EU population: a clear case of an economy-environment clash.