The order comprises the Sovereign and ordinary, additional and honorary members. The ordinary membership is limited to 20 living members, and at any time there may be fewer than 20. Additional members may be appointed to commemorate important royal, state or national occasions, and such appointments were made in 1990 for the 150th anniversary of the Treaty of Waitangi, in 2002 for the Queen's Golden Jubilee, in 2007 for the 20th anniversary of the institution of the Order, in 2012 for the Queen's Diamond Jubilee, in 2022 for the Queen's Platinum Jubilee, and in 2023 to mark the coronation of King Charles III. Additional members have the same status as ordinary members. Honorary membership is for citizens of nations of which the Sovereign is not head of state.[1] Members are entitled to the post-nominal letters "ONZ".
Appointments to the order are made by royal warrant under the monarch's sign manual on the prime minister's advice. The order is administered by a Secretary and Registrar (the Clerk of the Executive Council).
The insignia is made up of an oval medallion of the coat of arms of New Zealand in gold and coloured enamel, worn on a white and ochre ribbon around the neck for men or a bow for women on their left shoulder.