Rodney Graham "Rod" Sims AO (born 1950) is an Australian economist and former public servant. Sims served as chair of the Australian Competition & Consumer Commission (ACCC), Australia's competition regulator, from 1 August 2011 to 20 March 2022. Described as "the most feared man in Australian business" by the Australian Financial Review, Sims was the longest serving ACCC chair in the agency's history.