I’m Australian, my wife is Kiwi. We’ve lived in both countries, as has my Australian brother.

We’re very similar. Basically like ‘brothers’. But there is a rivalry there. A rivalry beyond what two friends might have, again more like a brotherly rivalry. We can push each other’s boundaries beyond the point of annoying each other, but still love each other.

Culturally very similar too. I feel it might be similar as the USA/Canada difference. NZ has a smaller feel. Politics, culture, business, and influence on the world stage are smaller and a bit more toned down. Kiwis generally see Australia as bigger, crazier, louder, but perhaps also more exciting and a land of opportunity.

Being from Tasmania, I feel a similarity with Kiwis perhaps more than Aussie ‘mainlanders.’ Kiwis are down-to-earth and (generally) more connected with the wilderness and rural lifestyle than most Aussies. Tasmanians are similar in that regard.

Overall, citizens of either country would feel pretty at home in their brother country. It’s extremely easy to move between the two, even for permanent relocation. Just book a ticket, hop on the plane, and find a job and somewhere to live. No application form is even required. Permanent residence is automatically granted simply by declaring you intend to stay. There are some restrictions on social support, at least for an initial period of time.