This master?s thesis empirically investigates if the European Union Emissions Trading Scheme (EU ETS) has an impact on the performance of companies. First, the most important determinants of of the scheme are presented. After that, the methods how the extension of emission trading can be balanced in the annual reports of companies are presented. The next section gives an overview of the literature regarding the impact of emission trading on company performance. This overview is given for two reasons: First, the current state of research should be shown; second, different methods how this impact can be empirically measured are explored. Besides some pilot investigations, the main method used in the empirical investigation of this master?s thesis is the linear regression analysis. This analysis is conducted by a multiple regression model and by two different panel regression models (fixed effects model and random effects model). The first part of the analyses focuses on the determination, evaluation, and the aggregation of data and on the description of all methods used. The empirical investigation covers data from about 2,500 companies located in six selected countries (France, Germany, Italy, Poland, Spain, and the United Kingdom). The sample period goes from 2008 to 2011. According to the results of the multiple regression models, to some extend impact of emission trading on company performance can be determined in the expected direction. The models also contain country- and sector-specific variables. Their impact on company performance is lower than expected, though. Next, the models are calculated after dropping insignificant variables and on the country level as well. Afterwards, the same analyses are conducted with the two panel regression models and their results are compared to those of the multiple regression model. Finally, all results are interpreted.