The NPC (National Provincial Competition) has always been New Zealand's premier domestic competition and was generally played between August and October every year. Twenty seven teams, each representing a provincial union, made up the competition across three divisions.
In 2006 the ITM Cup was introduced, with it's format evolving throughout the years.
The ITM Cup has been a feature of New Zealand rugby since 2006. It has changed the way it is played a number of times over the years.
Winners receive four competition points; if the game was a draw two points are awarded to each team. The Rugby union bonus points system is also used, where any team scoring four or more tries, and/or losing by less than seven points, receives an extra competition point. The top four teams at the end of the round-robin phase then played semifinals – the first placed team hosting the fourth placed team, and the second placed team hosting the third placed team. The two winners then played the final at the home ground of the top surviving seed.
In 2013, the ITM Cup has 2 Divisions - the Premiership and the Championship. Each Division has seven teams in it. Within this framework there is a unique format whereby teams will play all other teams in their own Division as well as four of the teams from the other Division. This keeps up some of the long established, traditional provincial rivalries.
New Zealand's provincial unions are (from north to south): Northland, North Harbour, Auckland, Counties Manukau, Thames Valley, Waikato, Bay of Plenty, East Coast, Poverty Bay, Hawke's Bay, King Country, Taranaki, Manawatu, Wanganui, Waiararapa-Bush, Horowhenua-Kapiti, Wellington, Nelson Bays, Marlborough, Buller, West Coast, Canterbury, Mid Canterbury, South Canterbury, North Otago, Otago and Southland.
The style of rugby differs as you travel around the country.
South Island teams tend to base their game around the forwards, mainly because of wet, heavy grounds. Teams in the North Island are better known for their expansive play with conditions more suited to running rugby.
Some of the more remote unions, like the East and West Coasts, are famous for unique and free-spirited styles all of their own.
The NPC (now ITM Cup) has been contested since 1976, but has changed in format several times since then. In the first year, Division One comprised seven North Island teams and four from the South Island, with the remaining provinces contesting a split second division, where South Island teams played each other and North Island teams did the same.
The lowest-placed Division One team (South Island) played the winner of Division Two (South Island) in a promotion / relegation battle, thus keeping four South Island teams in Division One.
The lowest-placed Division One side (North Island) was automatically relegated, and the winner of Division Two (North Island) was automatically promoted. But Taranaki found in 1979 that they were relegated after finishing ahead of three South Island teams.
The format continued until 1985 when Division Three was introduced, split between islands in the same way. The bottom-placed team was relegated automatically from Divisions One and Two, and the winner of Division Two was automatically promoted.
The two winners from each island section of Division Three played off for promotion, which led to North Harbour's promotion to Division Two only a year after the union was formed.
Alongside the provincial competition, and often between teams from different divisions, another battle takes place. In 1902 the governor of New Zealand, the fifth Earl of Ranfurly presented a trophy shield to Auckland, who were undefeated in provincial competition that year.
The Shield has since become known as the Ranfurly Shield, or Log of Wood, and is played for when the holders accept challenges from other unions, scheduling home games to defend it.
The significance of the Shield is immense. Just to play for it, no matter whether your team wins the challenge or loses by a big margin, is regarded as a huge privilege.
The fervour and festival atmosphere of the clashes is legendary, and the celebrations that have marked successful challenges by underdog lower division sides are remembered as red-letter days by those provinces for decades to come.
Lowly Marlborough upset Canterbury in the first challenge of 1973, and then put it up in Blenheim against all-comers for seven straight games before South Canterbury took it to Timaru, albeit briefly.
Every year, along with more fancied sides, Division Two and Three sides have an opportunity to challenge for the Shield. It's a big occasion for both players and supporters.
In 2013 Waikato have already defending the Shield against Horowhenua-Kapiti and East Coast, and the regular season's first Ranfurly Shield challenge will see the Northland Taniwha have the first tilt at wrestling 'the Log o' Wood' off the summer guardians, the Mooloos.