Article by Jean-Pierre Jeantheau about the assessment of low literacy levels in adults in France. The development of tools to assess low literacy levels in adults is fairly recent in France. It was inspired by recognition of the need to implement a national literacy policy and to encourage cooperation between stakeholders. The system is mainly designed to supply information to help manage public policies, even if it also assesses other subjects. It concentrates on the fraction of the population that is the focus of a public policy.