Today there are 16 million slaves in business supply chains. The UN Guiding Principles on Business and Human Rights (UNGPs) confirm that every company is responsible for respecting human rights in its own operations and supply chains. Based on the UNGPs, modern slavery due diligence has widely been recognized as an effective measure to tackle modern slavery. Modern slavery due diligence is a continuous process including the identification of actual and potential modern slavery risks, the implementation of an adequate response mechanism, monitoring of the effectiveness of the adopted measures and public disclosure of the due diligence process.