Prime Minister Scott Morrison has announced the reappointment of two department secretaries; Michael Pezzullo to Home Affairs, and Chris Moraitis to the Attorney-General's Department.
The announcement was made on Wednesday evening, with the prime minister lauding both men on their past achievements. Their terms are expected to last five years.
"Mr Pezzullo has served as the first Secretary of the Department of Home Affairs, the creation of which was one of the largest restructures of Australia's national security apparatus since Federation," Mr Morrison said.
"As secretary of the Attorney-General's Department, Mr Moraitis has overseen a range of significant reforms in Australia's law and justice sector."
Mr Pezzullo has served as Home Affairs chief since October 2014, while Mr Moraitis was first appointed the Attorney-General's Department boss in September 2014.
Mr Pezzullo was the target of a no-confidence petition by public sector union members in April this year, which called for an end to years of "waste, mismanagement and chaos" at the former Department of Immigration and Border Protection.
In August, he said the public servant who leaked a top secret document he authored should be sent to jail.
Mr Moraitis has put emphasis on the need for the public sector to be willing to change quickly alongside a new reliance on big data and rapid technological advancement.
"[The Attorney-General's Department has] been ... dealing with social media companies on the internet, terrorism, massive challenging new laws in the national security space, dealing with societal challenges like elder abuse," he said last year.