Due diligence is at the heart of the United Nations Guiding Principles on Business and Human Rights, which establish the main parameters internationally for considering corporate responsibility for human rights violations. However, the Guiding Principles invoke two different concepts of due diligence: the first is a process to manage business risks and the second is the standard of conduct required to discharge an obligation. In this article, we show that the Guiding Principles invoke these two concepts without explaining how they relate to each other. This confusion creates uncertainty about the extent of businesses’ responsibility to respect human rights and uncertainty about how that responsibility relates to businesses’ correlative responsibility to provide a remedy when they infringe human rights. On this basis, we propose and justify an interpretation of the Guiding Principles that clarifies the relationship between the two concepts of due diligence.