During the last decades, the relationship between economic growth and environmental quality has generated a strong controversy among environmental academicians. The main debate is focused on responding a specific and direct question: will the economic development intensify seriously the environmental damage? In the last two decades, some studies suggest that some pollutants follow an inverse-U-shaped pattern relative to countries income. This relationship has been called the ‘Environmental Kuznets Curve’ (EKC). The EKC can be easily described in the following way. Initially, income growth leads to an increase of the environmental degradation but, beyond some threshold level, additional increments of income will allow an environmental improvement. This paper lays out a simple model of the air pollution-income relationship for a panel of 23 European countries over the period 1992-2003. The results show a strong evidence of an EKC. The remainder of this article is organized as follows. After an introduction, the next section provides a brief overview of previous studies. Section 3 presents the EKC estimation with the econometric method used in the study. Also, the data are analysed and the obtained results are presented. Finally, in section 4, we present the summary and conclusions of this study.