由各締約方政府授權其交通管理部門按照公約中規(guī)定的式樣向出國旅行的本國駕照持有人簽發(fā)一種證明文件，來向其他國家的交通管理機構證明該駕車人擁有該國頒發(fā)的合法駕駛執(zhí)照。這個證明文件在公約中被稱作International Driving Permit，簡稱IDP，中文里翻譯成“國際駕駛執(zhí)照”，或“國際駕照”

國際駕照不是一個駕駛執(zhí)照。它只是由駕駛員本國的官方機構或經(jīng)其授權的其他機構根據(jù)該國政府所參加的聯(lián)合國道路交通公約、以公約中規(guī)定的標準式樣、用英/法/俄/中/阿拉伯/日等多種語言為駕駛員出具的證明該駕駛員持有該國有效駕照的一份證明，其主要通途是幫助其他國家的警察讀懂駕駛員的姓名、地址、準駕車型等必要信息。

http://baike.baidu.com/view/322324.html?wtp=tt

這是新西蘭道路交通局的一些解釋
a current and valid* overseas driver licence or international driving permit

*A current and valid overseas driver licence means that your licence allows you to legally drive in your own country. If you are disqualified from driving or your licence is currently suspended, expired or revoked, then you are not allowed to drive in New Zealand.

If you do have a current and valid overseas driver licence or international driving permit, you can drive using that for a maximum of 12 months from the date you arrive in New Zealand. Note: if your overseas licence or permit isn't in English, you must carry an accurate translation.