Sonny Bill the only 'rookie' for NZ
Williams is the only newcomer to the New Zealand side named to play in the Wellington round of the World Sevens series.
The serial code-hopper has shifted between rival Rugby codes, League and Union, in recent years as well as dabbling in boxing, where he has won all seven of his heavyweight bouts.
He was a member of the New Zealand team that won the 2011 and 2015 Rugby Union World Cups and the New Zealand team beaten by Australia in the Final of the 2013 Rugby League World Cup.
However, he has said he rated becoming an Olympian as the greatest feat an athlete could achieve.
"As a rugby player you strive to be an All Black, win a World Cup, win a Super Rugby title and as a league player, for myself you strived to win a comp," Williams said.
"I'm lucky enough to have achieved that, but as a sportsman, most would like to go to the Olympics and I haven't achieved that."
The New Zealand team to play in the Wellington leg of the Sevens World Series also includes Akira and Rieko Ioane, who will be the first brothers to play together in one tournament for New Zealand.
Ardie Savea, who last played Sevens for New Zealand in 2012, returns to the side after impressing in the 15-a-side game with the Wellington Hurricanes in recent years.
Blues wing Ben Lam last played for New Zealand at the Commonwealth Games in Glasgow in 2014, while Kurt Baker makes his return having last played in South Africa in 2014.
New Zealand: Kurt Baker, Sam Dickson, Akira Ioane, Rieko Ioane, Gillies Kaka, Ben Lam, Tim Mikkelson, Augustine Pulu, Ardie Savea, Regan Ware, Sonny Bill Williams, Joe Webber.
