Organized breast cancer screening via mammography was rolled out nationwide in France in 2004. Women still have the option of undergoing screening upon referral by a healthcare professional (known as individual screening). By comparing data from the General Sample of Beneficiaries (EGB) with that from the Sénolog database of the Senology Observatory, the share of individual screening in the target population could have been 10% in 2009, bringing the overall rate of women’s participation in screening to 62% (of which 52% was for organized screening). Pathology follow-up or case detection, meanwhile, would concern 7 to 8% of women. Analysis by age group based on the EGB showed that the overall mammography rate increased sharply after age 50, following the first invitation, but then plateaued, before declining after age 70 (50.7% at age 74). The databases used do not allow for the complete reliability of this estimate to be guaranteed. To improve it, the coding of mammograms in the Common Classification of Medical Procedures should be modified, all radiologists practicing breast imaging should be included in the Sénolog database, and quality control should be implemented regarding the reporting of the circumstances under which mammograms are performed. (R.A.)