This guide examines the responsibilities of private sector lawyers in avoiding and addressing, preventing and mitigating adverse human rights impacts on tenure right holders when advising on agricultural investments. These responsibilities arise under international standards for the protection of legitimate tenure rights, including the UN FAO Voluntary Guidelines on the Responsible Governance of Tenure of Land, Fisheries and Forests in the context of national food security (VGGT), as considered within the framework of international human rights laws which underpin aspects of those standards. In the light of the United Nations Guiding Principles on Business and Human Rights (UNGP), the guide considers the dual responsibility of lawyers in this context: (1) through the impact of these standards on the professional duties of the lawyer (including in-house counsel) towards the investor client and (2) through the impact on the law firm’s responsibilities as a business in its own right, in the light of its corporate social responsibility (CSR) commitments. The guide examines the requirements for due diligence in this context and makes a number of recommendations to promote compliance with UNGP on behalf both of the investor client and of the law firm, considered as a business in its own right.