The Occupational Health Department of the InVS has established and coordinates a program to develop crop-exposure matrices tailored to the agricultural population in France: the Matphyto program. In the agricultural sector, the specific characteristics of exposure to plant protection products—the use of numerous products, significant changes over time in their applications, and specific usage patterns depending on the crop, etc.—require the creation of matrices linked not only to job titles, as in other types of industrial matrices, but also to the type of crop. This is the objective of the Matphyto program. Its potential applications are numerous, ranging from surveillance to health research: -- describing the prevalence of exposure to plant protection products; -- assisting in the identification of past occupational exposures that may be useful for medical and social care; -- assisting in the individualized assessment of exposure to plant protection products during epidemiological studies. The presentation of the general characteristics of the Matphyto program is accompanied by three matrices concerning the cultivation of fruit trees, potatoes, and grapevines, and the use of arsenic-based pesticides. (R.A.)