This paper assesses the convergence in eco-efficiency of a group of 22 OECD countries over the period 1980–2008. In doing so, three air pollutants representing the impact on the environment of economic activities are considered, namely, carbon dioxide (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">$${\text{ CO}}_{2}$$</EquationSource> </InlineEquation>), nitrogen oxides...</equationsource></inlineequation>