2006–07 IRB Sevens World Series was the eighth of an annual series of rugby union sevens tournaments for full national sides run by the International Rugby Board since 1999–2000.
New Zealand won the 2006–07 series by winning the final tournament in Edinburgh. In that event, the then-defending series champions Fiji would have clinched the season crown by defeating Wales in the Cup quarterfinals. However, a Wales upset win opened the door for New Zealand to take the season crown by winning the Cup in Edinburgh, which they proceeded to do.
Sevens is a stripped-down version of rugby union, with seven players on each side rather than fifteen. Games are much shorter, seven or ten minutes each half, and tend to be very fast-paced, open affairs. Sevens is traditionally played in a two-day tournament format; however, the most famous event, the Hong Kong Sevens, is played over three days.
The Australia and Scotland events are new for 2006-07. The Australia event effectively replaces Singapore, and the Scotland event effectively replaces the Paris Sevens.
In a normal event, 16 teams are entered; in Hong Kong, 24 teams enter. In each tournament, the teams are divided into pools of four teams, who play a round-robin within the pool. Points are awarded in each pool on a different schedule from most rugby tournaments—3 for a win, 2 for a draw, 1 for a loss. The first tiebreaker is the head-to-head result between the tied teams, followed by difference in points scored during the tournament.
Four trophies are awarded in each tournament, except for Hong Kong. In descending order of prestige, they are the Cup, whose winner is the overall tournament champion, Plate, Bowl and Shield. In Hong Kong, the Shield is not awarded. Each trophy is awarded at the end of a knockout tournament.
In a normal event, the top two teams in each pool advance to the Cup competition. The four quarterfinal losers drop into the bracket for the Plate. The Bowl is contested by the third-place finishers in each pool, while the Shield is contested by the last-place teams from each pool.
In Hong Kong, the six pool winners, plus the two highest-finishing second-place teams, advance to the Cup. The Plate participants are the eight highest-ranked teams remaining, while the lowest eight drop to the Bowl.