Despite being banned by law, slavery and slavery-like practices remain widespread in Mauritania, with thousands of men, women and children – most of whom belong to the marginalized Haratine ethnic group – still trapped in servitude. To a large extent, impunity for these crimes has been enabled by the failure of authorities to take action against the perpetrators, leaving victims unprotected and with little or no access to justice. To address this Minority Rights Group International (MRG), in partnership with Mauritanian NGO SOS Esclaves and Anti-Slavery International, has for years been working to secure recognition of these rights violations and ensure authorities take concrete measures to implement anti-slavery legislation, including adequate investigation and prosecution of those responsible. While there have been some positive steps in recent years, including the passing in 2007 of the country’s first anti-slavery legislation, implementation and enforcement of its provisions have been almost non-existent. In November 2011, in the first prosecution under the 2007 Anti-Slavery Law, Ahmed Ould El Hassine was found guilty of holding two brothers, Said and Yarg Ould Salem, in slavery and depriving them of schooling. Despite this apparent milestone, however, the sentences imposed were well below the minimum terms stipulated by the law and the slave master was subsequently released on bail just four months after his conviction. In response, MRG and SOS Esclaves brought a case before the African Committee of Experts on the Rights and Welfare of the Child. In December 2017, the Committee ruled that Mauritania had failed to take adequate measures to prevent, prosecute and remedy slavery and found multiple violations of its obligations to protect children’s rights under the African Charter on the Rights and Welfare of the Child. The background and implications of this groundbreaking ruling are discussed in detail in this briefing. In light of a subsequent decision by the Mauritanian Supreme Court in April 2018 in relation to the case of Said and Yarg, which apparently failed to consider the Committee’s ruling, it is more important than ever to raise awareness about the proper application of anti-slavery laws in Mauritania for the benefit of other slavery victims.