Introduction. A pilot study was conducted in 2007–2008 to assess the feasibility of an epidemiological surveillance system for asthma based on a network of occupational physicians and to estimate the prevalence of asthma, its severity, and its control by industry sector and occupation. Method. Over the course of one year, in the Aquitaine and Midi-Pyrénées regions, data were collected during occupational health visits of employees randomly selected by physicians, using standardized questionnaires. Results. Of the 830 physicians in the two regions, 110 (13.4%) participated. They included 6,906 employees. The prevalence of current asthma was estimated at 5.4%, and that of lifetime asthma at 11.1%. Among employees with current asthma, 12.8% were uncontrolled, 49.3% were partially controlled, and 37.9% were controlled. Civilian employees and public servants, as well as those in the health/social services sector, had a significantly higher risk of current asthma. Conclusion. The pilot study demonstrates the feasibility of this surveillance system. It could be expanded to other regions or serve as a complement to cohorts currently being established. (R.A.)