Are you sure you're a citizen of 3 countries? I've not heard of that before. Perhaps you're confusing citizenship with residency? Australia, as do most Western countries allow dual citizenship i.e, You can be an Australian citizen and citizen of one other country only. So if you did want to become an Australian down the track, you would have to relinquish some of your existing citizenship's. For example, I am a permanent resident of Australia and a citizen of NZ and the UK (have NZ and UK passports). If I wished to become an Australian citizen (never seen the point in my case), I'd have to give up either the NZ or UK passport.