Possingham was the Queensland Chief Scientist from 2020 to 2022, where he provided high-level strategic science, research and innovation advice to the
Queensland Government and acted as an ambassador for science in
Queensland. Possingham is a member of the
Wentworth Group of Concerned Scientists, chaired the Australian Government's committees on
Biodiversity Hotspots, and on Biological Diversity, the Queensland Government's Smart State Council, and the
Wilderness Society's Wild Country Science Council. Possingham co-authored "The Brigalow Declaration" with Dr Barry Traill, used by Queensland Premier
Beattie to support an end to land-clearing in Queensland. Land clearance in Queensland was removing 500,000 hectares of native vegetation each year, and was responsible for 10% of Australia's greenhouse gas emissions; its cessation enabled Australia to meet its
Kyoto Protocol target. In 2009 he proposed devoting a proportionate fraction of gambling revenues to saving an endangered species, to be selected by a random drawing shown on television before the
Melbourne Cup. From 2016 to 2020, Possingham was the Chief Scientist of
The Nature Conservancy, a global conservation organisation with 400 scientists and 4000 staff, that has protected more than 40 million hectares of land and thousands of kilometres of rivers worldwide. ==Awards==