Objective - The objective of the surveillance system for pediatric ENT conditions is to estimate the incidence of acute episodes of nasopharyngitis, otitis media, tonsillitis, sinusitis, and laryngitis during the winter season in mainland France. Method - A sample of "observer" practitioners collects cases of the monitored conditions during their consultations. The incidence of the observed conditions is estimated. In addition to interactive and direct access to the data, results are available in real time on the website or via newsletters in the form of weekly reports at the national and regional levels. Results - This observatory operated during the 2005-2006 and 2006-2007 winters with a network of general practitioners, ENT specialists, and pediatricians. It enabled the reporting of a cumulative total of 388,685 consultations for the observed reasons for consultation over the two seasons. The number of consultations was estimated at an average of 18.6 million during the winter period for these conditions, or approximately 1.65 consultations per child per season. Conclusion - The Hivern@le-KhiObs observatory has quantitatively confirmed the very high frequency of ENT infections in children. It provides a better understanding of the prevalence of these conditions during the winter, thereby contributing to a more rational approach to these conditions in public health. (R.A.)