Australians and New Zealanders have fought side by side in world wars, can move without restriction between countries under the trans-Tasman arrangement and share a mutually beneficial free trade agreement.

Yet when it comes to each others' expatriates, Australia has been accused of treating Kiwis as second-class citizens.

And while prime minister-elect Tony Abbott might still be only a week into the top job, New Zealanders are already hoping that because his wife, Margie, is a Kiwi it will help influence change.

Under travel arrangements reached in the 1970s, expats can live, work and study in each country indefinitely. But legislative changes introduced by the Howard government 12 years ago - as well as amendments to several other laws thereafter - changed things.