Several conventional risk factors for stroke and cerebrovascular disease, such as hypertension, smoking, and atrial fibrillation, are widely recognized. Correct management of these modifiable factors significantly reduces stroke risk. We review the research evidence that depressive symptoms and increased atmospheric pollution are associated with an increased risk of stroke, and outline putative mechanisms that may account for these associations. The data on depression and stroke risk strongly indicate the need for treatment intervention studies. The design and implementation of intervention studies related to air pollution requires better understanding of the pathophysiologic mechanisms linking exposures to the onset of stroke. This issue of Environmental Neurology - Proceedings of the Meetings of the Environmental Neurology Club, held in Paris, France, 2-3 December 2005 and in Metz, France, 7 February 2007, under the aegis of the French Society of Neurology, The University of Metz, and the Environmental Neurology Research Group of the World Federation of Neurology (ENRG-WFN)