Overseas driver licence conversion
Overview
Overseas driver licence conversion is covered under the Land Transport (Driver Licensing) Rule 1999. Refer to sections 89 through 92.
Assuming you are from a "recognised" developed country (refer to the "Country Specific" list below to make sure your are from a country that is exempt from having to re-sit the test(s)) the basic procedure is to take into the Automobile Association (known locally as the "AA") shop your existing license, proof of address, ID (passport etc) and fill in a DL5 form in the shop. The cost is approximately $44.30.
Country Specific
Note that the exemptions only apply to class 1 and class 6. Goods vehicles licences must resit
People from the following countries need not sit the theory test:
http://www.legislation.govt.nz/regulation/public/1999/0100/latest/DLM1573020.html#DLM1573020
People from the following countries need not sit the practical test:
http://www.legislation.govt.nz/regulation/public/1999/0100/latest/DLM282614.html#DLM282614
Advice
If you want to transfer a car license at the same time there is only one charge, doing both separately will cost you twice as the administration work has to be done again.
Note this procedure is mainly for people coming to reside in New Zealand. If you are just visiting you should consider getting an International Driving Permit.