Various stakeholder groups are mounting calls for Boards of Directors to take sustainability into account while adhering to their legal duties to shareholders. This puts questions about fiduciary duty front and center. Careful legal analyses of such questions have been prepared over the past year by law firms all over the world. The collection of memoranda below will inform and enrich discussion among Board directors, and the lawyers who counsel them, about how changing circumstances near and far are affecting their ability to meet fiduciary duty requirements. Prof. Robert G. Eccles and Tim Youmans of Harvard Business School have led this collaboration which included the UN Global Compact, the American Bar Association’s Task Force on Sustainable Development and PRI, Their aim was to gather legal perspectives from law firms in a wide range of countries. Each participating law firm used a standard research template developed by Linklaters in the UK to structure their respective legal memo. The legal memos are posted below with the permission of the participating firms. To further grow the research, enquiries from law firms in countries that do not already have a legal memo are welcome. If you do not see your country listed and want to know if one is being prepared, please contact Ingvild Soerensen (firstname.lastname@example.org).