Raw materials assume different forms during their use and thereby develop a multiplicity of effects upon the political environment. This article demonstrates the method of sectoral mass flow analysis using the example of the raw material wood. Under conditions of limited resources, market analysis methods must change from single flow analysis in an open (unlimited) system to interactive flow analysis in a closed (limited) system. The method of the wood resource balance is introduced, with its basic elements of resource monitoring, bottom-up approach, data counterchecking and conversion factors. The method is applicable for manifold research topics. This is shown in three examples. The wood flow analysis represents a total resource assessment including all wood products in all process steps from forest to disposal. Based on the wood flow analysis, calculation schemes show how cascading factors can be calculated on a constant basis. Finally the CO2 effects of total wood use are calculated on a continuous basis. (C) 2014 Elsevier Ltd. All rights reserved.