This edition of SOFO examines the contributions of forests, and of the people who use and manage them, to the conservation and sustainable use of biodiversity. It assesses progress to date in meeting global targets and goals relating to forest biodiversity and describes the effectiveness of policies, actions and approaches for conservation and sustainable development alike, illustrated by case studies of innovative practices and win-win solutions. This volume does not aim to be a comprehensive treatise on forest biodiversity, but rather to provide an update on its current state and a summary of its importance for humanity. It is intended to complement The State of the World’s Biodiversity for Food and Agriculture, released by the Commission on Genetic Resources for Food and Agriculture of the Food and Agriculture Organization of the United Nations (FAO) in 2019, last year’s Global Assessment Report on Biodiversity and Ecosystem Services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) and the Global Biodiversity Outlook 5 of the Convention on Biological Diversity (CBD).