By way of example, under subpart 5, section 76 of the Incorporated Societies Act 2022, members of an ISCO must formally consent to be a member of the ICSO and abide by its rules, (which will invariably include those required to play the game, if the ISCO is affiliated to an NSO). Section 26 (1) (c) and (d) require an ICSO's Constitution to describe "how a person becomes a member" and "how a person ceases to be a member".
Additionally, an ICSO also a specific responsibility under section 79 of the Act to "keep a register of its members", including recording any changes "as soon as practicable after becoming aware" of them. The collection and storage of membership information by an ICSO must be undertaken in accordance with New Zealand's "privacy principles", under the Privacy Act 2020, (per section 80 (4) of the Incorporated Societies Act 2022).
An important point to note in amateur sport, is that NSOs are generally created by grassroots clubs as representative of ICSOs nationally who (in creating the NSO), have the objective of ensuring there is a common approach to playing and developing the game, for the benefit of participants. Generally, to play the game, a person must become a member of the ICSO first, with the register of members available to the NSO only for the purposes of ensuring that participants in competitions or teams organised by the NSO are "eligible", (by virtue of being ICSO members).
Where a sport is built on ICSOs, NSOs have no pre-emptive role in managing or administering ICSO memberships, as each ICSO will determine the unique basis on which a person can become a member of it, with different membership categories, involving both “on the field” and “off the field roles”.

In our opinion, the only role NSOs have with regard to ICSO membership is determining the criteria under which participants can play the game. (However, even this role generally requires ICSO approval. NSOs cannot unilaterally decide “who” can play the game, given every NSO is primarily a representative of its ICSO member affiliates).
There is no problem in an ICSO Committee contracting an agency (e.g., an online service) to act as a “membership agent”, provided that the agency is able to meet the ICSO’s regulatory obligations, (including recording the consent of the member to abide by the specific rules of the ICSO). Under New Zealand’s privacy regulations (the “privacy principles”), a membership agent can only collect data for the ICSO’s specific purpose, not for any other purpose (commercial or otherwise), without the express consent of the member being solicited by the agent.

In considering whether or not to engage a membership agent, an ICSO’s Committee should be aware that agents located offshore may not be bound by New Zealand regulations. Of paramount importance, each ICSO has the sole right as to "who" can become a member, in accordance with that ICSO's constitution.
The Association notes that the information contained and opinions expressed in this article should be used as general guidance only and are not a substitute for professional legal advice. As with all matters relating to law and regulation, the Association recommends that ICSOs seek independent legal advice where necessary.