His career has included: scientific advisor in the Office of Science and Technology Policy, White House; chief scientist, World Bank; chief scientific advisor, UK Department of Environment, Food and Rural Affairs; and strategic director for the Tyndall Center, University of East Anglia, UK.  He has chaired, co-chaired or directed the WMO/UNEP stratospheric ozone depletion assessments, Global Biodiversity Assessment, Millennium Ecosystem Assessment, UK National Ecosystem Assessment and its Follow-on, Intergovernmental Panel on Climate Change, the Intergovernmental Assessment of Agricultural Scientific and Technology for Development, the Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services, and UNEP’s Making Peace with Nature. Awards include a Knights Bachelor (2012), Companion of the Order of Saint Michael and Saint George (2003); Fellow of the Royal Society (2011), member of the American Philosophical Society (2020), honorary member of the AMS (2021), UN Champion of the World for Science and Innovation (2014), the Asahi Glass Blue Planet Prize (2010).