New Zealand - Passport & Nationality - Dual Nationality
New Zealand allows its citizens to hold Dual Nationality - that is, the right to become a citizen of a foreign country and to hold two (or more) passports.
For more specific information about some countries where you hold citizenship:
Under the nationality laws of some countries, a married person automatically has his or her partner's nationality. Children may also have a parent's nationality even if they were born abroad. If your wife, husband or child is visiting the country of your nationality, you should check with the country's consulate or high commission in the United Kingdom before you travel.