Labor's key campaign strategist has quit eight weeks after the federal election to return to the corporate sector.
ALP national secretary George Wright, who came to the role in 2011, has presided over the past two election campaigns and two party conferences.
Mr Wright said he hadn't come to the decision lightly and had discussed it with Labor leader Bill Shorten.
"It is time for me to spend more time with my family in my home town of Melbourne and seek new challenges and opportunities," Mr Wright said in a statement on Tuesday.
Mr Shorten said Mr Wright had been central to the work of rebuilding Labor, growing the party's membership and engaging with supporters and volunteers in new ways.
"He's a tireless, creative campaigner every Labor person wants in their corner," Mr Shorten said.
Mr Wright left NAB to take on the Labor role in May 2011 and will return to the corporate sector in a senior corporate affairs role with BHP Billiton in Melbourne.
He served under Julia Gillard, Kevin Rudd and Mr Shorten.
"I know Bill will make a great Australian prime minister," he said.
The outgoing secretary played a central role in the defeat of the Howard government in 2007, working with the ACTU on its "Your Rights at Work" campaign.
He served as press secretary to Finance Minister Lindsay Tanner and Mr Rudd in the early years of the Rudd government.
