In-form Auckland, a star-studded Hawkes Bay and a reinforced Taranaki are the favourites among the 16 men's teams at this weekend's Bayleys National Sevens in Rotorua.
The two-day tournament, part of the Herald Summer of Sevens, returns to the Bay of Plenty city after a decade in Queenstown.
Auckland, with current or former internationals Ben Lam, Tutu Tairea and Orene Ai'i to the fore, triumphed in the Northern Region Sevens and Bay Engineers Supplies Provincial Sevens in recent weeks.
Auckland coach Paul Feeney says the team is in good shape as they hunt a 13th national title.
"There has been a massive turnaround in personnel but this team is working very hard, there are no egos and they are enjoying playing together," said Feeney.
"We're under no illusions though, the nationals is a tough competition and there are a lot of contenders."
Auckland line up in Pool B with Wellington, Poverty Bay and Southland.
However, the return of key players for Hawkes Bay and Taranaki strengthens their chances, while Canterbury, Waikato, Manawatu, Wellington, North Harbour and Northland are also contenders.
Hawkes Bay welcome back Gillies Kaka, the 23-year-old who recently featured in the IRB's showcase of the quickest feet in Sevens, and Ihaia West, who turns 22 next week.
Teammates include Tom Iosefo, scorer of more than 60 tries for Samoa Sevens, one-cap Samoan Neria Fomai and Trinity Spooner-Neera, who has played for New Zealand Schools, Sevens and U20s.
Defending National Sevens champions Taranaki are bolstered by the return of captain Warwick Lahmert and sparkling playmaker Beaudein Waaka.
On top of the 20 or so international players on show at the Rotorua International Stadium, the tournament is likely to reveal stars of the future.
School-leavers Akira Ioane, an athletic loose forward from Auckland Grammar, Mitchell Hunt, a talented playmaker out of Nelson College, and Solomona Alaimalo, a strapping centre from St Bede's College, are among those expected to make an impression. Ioane and Hunt join an Auckland team much changed from 2012.
The return to Rotorua for the 40th edition of New Zealand's premier domestic tournament also bodes well for the Auckland women; they won the last National Sevens held there in 1998.
However, reigning champions Manawatu start as hot favourites after they beat Auckland 40-5 last weekend in Mt Maunganui.
New Zealand Women's Sevens coach Sean Horan is using the national sevens to finalise his squad of 17 contracted players.
"This tournament will be the last big push for a lot of players to earn a spot in the first ever New Zealand Women's Sevens contracted squad, so I've been urging those players in contention to work hard before we announce the squad," Horan told allblacks.com.
"Judging from the regional tournaments to date, I'm expecting the women's teams to be extremely competitive at the nationals.
"The standard of women's sevens rugby is remarkable right now and there is definitely some great talent out there."
Manawatu, with Sarah Goss, Selica Winiata and Kristina Sue among their stars, will be tough to beat, however Auckland is bolstered by the return of national captain Huriana Manuel and IRB Player of the Year Kayla McAlister.
"Having New Zealand reps in the team certainly helps drive the training and work ethic to a high standard," Auckland coach Peter Walters said.
"The squad has worked hard over the past four months and there have been some great improvements in skill and game knowledge."
Waikato and Canterbury are expected to make the semifinals with a sprinkling of national players in each team.
Ten women's sides, up from six last year, will play in two pools of five with the top four going through to the quarter-finals.
Fine weather is forecast for both days at the Rotorua International Stadium with matches starting at 12.05pm.