Mortality data in the province of Modena 1987-1996 show an excess for lung cancer in the municipality of Fiorano Modenese. In order to characterize the risk factors involved, a case-control study was carried out. Exposure to particulate matter was associated with lung cancer (OR 2.4 IC 95% 1.2-4.7). In the meantime, also as a consequence of this study, Fiorano Modenese Council started actions and obligations to control air pollutants emissions. The study is described as an example of good integration between local epidemiological knowledge and preventive interventions by Local Administration; problems and doubts surfacing from this experience are also pointed out.