The political discussion is very much concerned with the question whether measures of environmental policy will mainly cause negative economic effects or positive economic effects. In most cases a specific environmental action will have both effects. Therefore it is necessary to try to evaluate the economic net effect of such measures. In the study which is described below an econometric model was specified on the basis of a time-series of input-output-tables which allows a simultaneous evaluation of positve and negative effects. The paper is organized as follows: In section 2 the general concept of the model will be described. In the following paragraphs 3, 4, 5 and 6 the different parts of the model: final demand, production, prices, and income are discussed and the main estimation results are documented. In the conclusion some results of the first simulation experiments are given. (orig.).