This article is a critical analysis of the following study: Fischer P, Hoek G, Brunekreef B, Verhoeff A, van Wijnen J. Air pollution and mortality in the Netherlands: are the elderly more at risk? Eur Respir J Suppl. 2003 May;40:34s-38s. The authors compared, across different age groups, the short-term associations between mortality and various urban air pollutants. Despite some uncertainties, this article, thanks to its age-group approach, identifies older adults as a more vulnerable population. This finding is consistent with the international literature and confirms the need to target prevention messages toward this population. It would now be interesting to conduct further analyses by age group to determine whether the time lag between exposure and effects varies by age, and also whether this lag differs depending on the causes of mortality studied.