As per Immigration Licensing Act of 2007, every adviser must have an immigration licence. Compulsory licensing started in 2009. Licenses are granted by the Immigration Advisers Authority. To be granted the licence, one must either have a long term experience or a degree and some experience in immigration advice. Lawyers and some Chartered Accountants are exempt from IAA licensing. Every licence must be annually renewed.
There is a limited number of cases when immigration advice can be provided without holding a licence. They are friends and family members, diplomatic consular or New Zealand Member of Parliament. More information on who can or cannot provide immigration advise can be found on IAA website.
I have been holding Immigration Adviser licence since April 2009. My licence was granted based on my experience (first cases took place in 1997). My first New Zealand work visa was for a position of Immigration Consultant. It was a bold move and it took Immigration New Zealand almost half a year to realize that visa must be granted 🙂