In the book, we examine the necessity and impacts of measures adopted under the greenhouse gas emissions target in the Europe 2020 growth strategy in the EU-15 states. For testing the necessity of the measures, we use the Environmental Kuznets Curve (EKC) hypothesis for carbon dioxide (CO2) emissions as the theoretical framework, the Autoregressive distributed lag model as the econometrical technique and annual data from 1970 to 2010 (1991 to 2010 in the case of Germany). The existence of the EKC is detected in Belgium, Denmark, France, Germany, Netherlands, Spain, Sweden, and the United Kingdom. However, only in Denmark the EKC hypothesis is supported significantly (on ten percent level of significance). Following the main implication of the EKC hypothesis, only in Denmark is the economic development sufficient enough to safeguard environmental quality.