This note is an annex to the Working Group’s General Assembly report, A/73/163, which takes stock of business and government action to advance the implementation of corporate human rights due diligence as set out in the Guiding Principles on Business and Human Rights: Implementing the United Nations “Protect, Respect and Remedy” Framework. The report highlights emerging good practices that should be built upon and scaled up in order to address gaps in current practice. The present note seeks to complement the report’s chapter II, which addresses key features of human rights due diligence and why it matters. It provides further background to the concept of human rights due diligence and a list of answers to some frequently asked questions. Further considerations are clarified in OHCHR’s Interpretive Guide on the corporate responsibility to respect human rights. A separate companion paper (companion note II) by the Working Group contains lessons from getting started on corporate human rights due diligence and an overview of tools and resources. Scaling up effective human rights due diligence in business practice worldwide is a key objective for the Working Group. Further information on its thematic work on this topic is available at https://www.ohchr.org/EN/Issues/Business/Pages/CorporateHRDueDiligence.aspx.