Simon Longstaff began his working life on Groote Eylandt in the Northern Territory of Australia. He is proud of his kinship ties to the Anindilyakwa people. After a period studying law in Sydney and teaching in Tasmania, he pursued postgraduate studies as a Member of Magdalene College, Cambridge. In 1991, Simon commenced his work as the first Executive Director of The Ethics Centre.

In 2013, he was made an Officer of the Order of Australia (AO). Simon is an Adjunct Professor of the Australian Graduate School of Management at UNSW, a Fellow of CPA Australia, the Royal Society of NSW and the Australian Risk Policy Institute.