Simon served as Chair of the Species Survival Commission (SSC) for the International Union for Conservation of Nature (IUCN) from 2008 to 2016. He has undergraduate and doctoral degrees from the University of Cambridge, with fieldwork in Tanzania and Cameroon. He has 40 years of experience with the IUCN and the SSC, having started work on the African Bird Red Data Book in 1983. He joined the IUCN Secretariat in 1986, and was Head of the Species Programme (1990-2000), Acting Director General (2000-2001), Head of the Biodiversity Assessment Unit (2001-2005), and Senior Species Scientist (2005-2008). He was elected as Chair of the SSC at the IUCN World Conservation Congress in Barcelona in October 2008. Simon recalls “My interest in conservation started as a child, earlier than I can remember. A fascination for wild animals and plants has always been in my blood. A career in conservation was the only option for me. The SSC is in many senses my home.” He played a key role in developing the quantitative IUCN Red List Categories and Criteria, and he conceived and led the Global Amphibian (2001-2004), which highlighted the worldwide amphibian crisis. He has also produced numerous high impact reports and books. While SSC Chair, Simon was instrumental in founding the Amphibian Survival Alliance and the IUCN SSC Asian Species Action Partnership (ASAP). After completing his term as SSC Chair, he joined Synchronicity Earth as Director of Strategic Conservation (2017-2020), and then became Executive Director of A Rocha International (2020-2022). In 2020 he won the Blue Planet Prize in recognition of his work on the IUCN Red List of Threatened Species, and his promotion of amphibian conservation. He is currently Advisor to the SSC Steering Committee, Chair of ASAP, Chief Scientific Advisor to Synchronicity Earth, Senior Advisor to Conservation Programmes for A Rocha International, a member of the International Selection Panel for Future For Nature, and a board member of Fondation Segre, Mandai Nature Fund, and Mandai Nature International.