Wayne Smith will step down as New Zealand assistant coach after the Rugby Championship.
The former fly-half played 17 Tests for the All Blacks and first took up a coaching role with the world champions back in 1998.
Smith, who turned 60 last month, has decided to take a break from rugby union when the Rugby Championship finishes in October.
"It's unbelievable to think that I've been involved in playing and coaching with the All Blacks for 20 years, a third of my life." said Smith.
"I've had an incredible time and shared in some fantastic experiences. But it's time to hang up my coach's whistle for a while, take a bit of a hiatus, freshen up and spend some more time with my wife Trish and our family."
New Zealand Rugby will advertise for a replacement for Smith and All Blacks head coach Steve Hansen said his long-serving number two will be a hard act to follow.
Hansen said: "I've been lucky to have spent a lot of time with Wayne Smith over the years, firstly as a player being coached by him and, best of all, coaching alongside him with Canterbury, the Crusaders and the All Blacks.
"He's a man I have a huge amount of respect for and it's been an absolute pleasure working alongside him. However, it's an even greater honour to be able to call him a mate.
"He has an unrelenting passion for the game, he's always been innovative, prepared to speak his mind, and he's never allowed himself to stop learning. He's always been willing to share himself with others and be open to their ideas.
"Smithy has been a major contributor to not only New Zealand Rugby but also world rugby. Wayne has been such a wonderful ambassador for our game and our country as well.
"I knew it was time to let him finish when he asked my wife to convince me to stop pressuring him into re-signing. It's with sadness that we let him go, but it's also with the confidence of knowing that he has left an everlasting legacy which is all one can expect of an All Black man. Smithy is undoubtedly a true All Black legend."