This paper focuses on the roles of both shareholders and companies in promoting and supporting gender diversity on Boards. It should be viewed in the context of the ICGN Global Corporate Governance Principles (2009) and other ICGN guidance (see Annex 6.3). It sets out the ICGN’s view on gender diversity as an important governance issue in contributing to the effectiveness of Boards and, ultimately, the long-term sustainability of companies.