Austin is a retired Army general and is the former commander of the US Central Command.
He has worked closely with Biden in the past. While Biden was vice president, Austin served as the vice chief of staff of the Army and commanding general of US forces in Iraq, and later the commander of CENTCOM. Biden and Austin had discussions on a range of issues, including those in the Middle East and Central and South Asia.
Austin would need a congressional waiver to be confirmed for the civilian post because federal law requires seven years of retirement from active duty before taking on the role. Austin retired from active-duty service only four years ago.