Dr Wendy Southern PSM, during her Australian Public Service career held senior positions across a number of departments and agencies including SES Band 2 and 3 positions in the Department of the Prime Minister and Cabinet, Department of Immigration and Citizenship (later Border Protection), the Department of Health and Ageing and the Australian Security Intelligence Organisation. Wendy's responsibilities ranged across policy development and implementation, program management, compliance, whole of government coordination and chief operating officer roles. She was involved in senior governance frameworks in all of those positions.

Wendy was awarded a PSM in 2006 and the Outstanding Achievement in Public Administration Award in 2010.

Wendy retired from the APS in 2020 and is currently Chair of the audit and risk committees of the Parliamentary Budget Office and one of the intelligence agencies. She is also a member of the audit and risk committees of the Department of Finance, the Australian Federal Police and the National Archives of Australia and a member of the National Suicide Prevention Office Advisory Board.