Assessment of care supply in terms of medical labor force is difficult because of the disparity of available data. Using the medical specialty of pathology as an example, we present for the first time a demographic analysis based on the confrontation of main data sources. This study underlines some of the structural and dynamic problems which threaten the demographic stability of the specialty. The public service suffers from a lack of practitioners, especially in regional hospitals. Whereas one third of French pathologists work in the larger hospitals around Paris, in some other regions private services constitute the main component of the supply. Projections based on the aging phenomenon and a reduction in entry indicate a future problem in the renewal of generations of pathologists. The consequences of this programmed decrease in the number of French pathologists will be further exacerbated by the movement of the sex ratio in favor of women.