Brown still had a year to run on his contract with Huddersfield
Huddersfield Giants head coach Nathan Brown is to leave the Galpharm Stadium at the end of the season.
The 36-year-old took charge of the Giants at the beginning of 2009 and was named Super League coach of the year in his first campaign at the helm.
But he has now opted to return to his native Australia.
He told the club website: "It's purely a family decision. I don't have a job to go to nor have I even spoken to anyone back home about employment."
Last season, the former St George Illawarra boss guided the Giants to the Challenge Cup final and a third-placed finish in Super League.
As well as being named coach of the year, his side were named as Super League club of the year.
The Giants currently lie fourth in this year's Super League, with eight wins from their 13 games.
In April, Brown denied that he was set for a return to the NRL with Cronulla Sharks, telling BBC Radio Leeds: "At this stage I'd say I'm going to be at the Giants and that's the way I'll keep working and recruiting towards doing the best for the Giants."
But after an apparent U-turn he explained: "This decision is not about my professional life, it's about my family's life.
"To say I have enjoyed my time here - and will continue to do so - is an understatement. It's been great for us but I just have to make this decision now for the benefit of everyone as the continued and relentless media speculation has been good for no-one.
"I will continue to give my absolute best to the club in every aspect of the job until the year end and assist them in going forward in the future in any way I can.
"Wherever I end up I will always look for the Giants results and be rooting for them."
Personal circumstances have meant that this has come a year sooner than either of us would have predicted or wanted
Huddersfield chairman Ken Davy
The club will now discuss Brown's successor at the next scheduled monthly board meeting.
Giants chairman Ken Davy said: "Of course we are very disappointed to receive Nathan's resignation, particularly as he has a year to run on his contract.
"We had read like everyone else the speculation floating around and Nathan has always been totally honest and upfront with us that he wished to return in due course to the NRL.
"Personal circumstances have meant that this has come a year sooner than either of us would have predicted or wanted.
"However there is no doubt that this has been an unsettling period for all concerned and now that the uncertainty is cleared up, we can all knuckle down to the immediate job in hand, which is bringing success to the Huddersfield Giants.
"I know that Nathan will do all he can to ensure that he goes out on a high."