Former Liberal defence minister Peter Reith has died aged 72.
Over his 17 years in parliament Mr Reith served under Malcolm Fraser, Andrew Peacock, John Hewson, Alexander Downer and John Howard.
Former prime minister John Howard has paid tribute to his "dear friend".
"The Liberal Party has lost a tireless champion of what it believes in," Mr Howard said.
"He played a major role in the successful reforms of the Howard government.
"I extend my deepest sympathy to his wife Kerrie and his four sons, and their families."
Mr Reith's former press secretary Ian Hanke released a statement on behalf of the family.
"It is with deep sadness that we confirm that following a brave battle with Alzheimer's disease Peter Reith died peacefully on the afternoon of 8 November 2022," the statement said.
"We are proud of his many achievements and his lifelong commitment to public service.
"A beloved grandfather, father, husband, brother, friend and respected colleague.
"He will be dearly missed and always cherished."
He was first elected as the member for Flinders in the 1982 by-election before being defeated in the general election the next year.
He was elected once again in 1984 and held the seat until 2001.
He was deputy leader of the Liberal Party from April 1990 to March 1993.
Mr Reith was a senior cabinet member of the Howard government, taking on the industrial relations portfolios from the mid-90's until the early 2000's.
Mr Howard said Mr Reith was a "great warrior for the Liberal cause".
As minister he was a key figure in the 1998 Waterfront dispute, one of the most significant moments in Australian industrial relations history.
"However contested the outcome of the 1998 Waterfront Dispute may have been, it was undeniable that world ranking productivity replaced ruinous behaviour which severely damaged some of the most productive businesses in Australia," Mr Howard said.
A bitter dispute between the Maritime Union and stevedoring business, Patrick, was triggered when the company entirely dismissed its union workforce and replaced it with a non-unionised one.
It was a fight Mr Howard described in his memoir as "the most bitterly fought domestic issue of my whole time as prime minister".
More than 1,400 dock workers were sacked, wharves were closed, and a seven-week strike began as Mr Reith and the Howard government controversially supported Patrick.
It wasn't the last controversy Mr Reith would face as a minister.
After being appointed defence minister in 2001, Mr Reith became one of the central figures in the Children Overboard scandal where Howard government ministers falsely claimed asylum seekers had thrown their children overboard in an attempt to gain access to Australia.
Mr Reith released photos purporting to show children in the water, but not long after his office was told those images were actually from a different boat sinking.
A senate committee later found that not only were children not thrown overboard and there was no evidence to support claims that they had been, but that Mr Reith had "deliberately deceived the nation" by not correcting the record during the 2001 election campaign.
Opposition Leader Peter Dutton said Mr Reith was a "stalwart" of the Liberal Party.
"Peter’s political legacy is extensive," Mr Dutton said.
"He was an architect of pivotal workplace reform which put the interests of employers and employees first."
Mr Dutton said the parliament would have an opportunity to reflect on Mr Reith's legacy.
"On behalf of the Coalition, I offer my heartfelt condolences to Peter’s colleagues, his friends and his family, especially his wife Kerrie, and four sons Paul, Simon, David and Robert," he said.
