In France as in other countries, prison faces the challenge of securing inmates’ reentry and preventing recidivism. Theoretically, prison work offers a direct opportunity to improve reentry prospects, but only one quarter of prisoners have access to work today in France, compared to 36% twenty years ago. This article provides a summary of the challenges at stake with prison work. It reviews the theoretical and empirical research on the impacts of rehabilitation programs and discusses the potentiel effects of prison work on social welfare. The article also makes the case that the supply of prison work and public spending in this area are insufficient in France, considering the externalities involved. Finally, the article develops public policy recommendations for prison work to deliver its full potential.