Ask Australian Michael Pirrie where home is, and he hesitates. Currently, of course, he lives in London. And, yes, after all these years away, he still owns a house in his native Victoria, though that's rented out.
But home? ''Well, really what I have is an email address,'' he says. ''You'd better put me down as being of 'no fixed abode'.''
Pirrie is executive adviser to the London Organising Committee of the Olympic and Paralympic Games (LOCOG), a plum job that involves working alongside its globe-trotting chairman, Sebastian Coe.
It's the latest big gig in an events management career that began 12 years ago, when Pirrie swapped journalism for a media job with SOCOG, organisers of the Sydney 2000 Games.
Since then he has been an organiser or working observer at almost every big multi-sport event held worldwide (see panel). The time, he says, has flown by.
''I've had so many wonderful experiences. Big events are very intense, the logistics very challenging. After all, each city or country is spending billions, putting its international reputation on the line.''
Pirrie is one of hundreds of Australians - many of them self-confessed ''big-event junkies'' -working on the London games at different levels, delivering a multitude of skills. They include:
''The queen of parades'' Di Henry OAM, a world-acclaimed torch relay expert, who is working with the London mayor, Boris Johnson, on the capital's 2012 events and celebrations; Jeremy Edwards, ''a country boy'' from Trangie, west of Dubbo, who is venue manager at the Greenwich equestrian centre, the latest in a series of Olympics jobs since Sydney 2000, and, Nicole Reynolds, the operations manager of the venue press team, which includes several other veterans of the Sydney 2000 campaign.
Other senior Sydney games officials to have assisted the London organisers include Sandy Hollway, David Churches, Jim Sloman, Bob Elphinston and Simon Balderstone.
Kevan Gosper (media) and John Coates (co-ordination), and Englishman Peter Ryan, (security), the former NSW police chief and security commander in 2000, are also closely involved via the International Olympic Committee.
And that's not all. As Eric Winton, of the Australian International Sporting Events Secretariat - an inter-state initiative to provide access to our big-event expertise - local companies also have a strong presence.
They include builders Lend Lease and architects BVN (athletes' village), technology specialists STI (hockey pitches), engineers SKM (basketball arena), event planners EPG and strategic planners MI Associates.
''There are areas we haven't got a look in,'' said Winton. ''But on the whole we've done well. In event management, our companies have a reputation for experience, expertise, flexibility and an ability to deliver.''
A ''gravy train'' then? Winton, who is already planning for the Rio de Janeiro 2016 games, prefers to talk of a ''caravan of Australian Olympic expertise'', moving ceaselessly across the burgeoning big-events market.
Similarly, itinerant Australians blench when described as big-event junkies.
Pirrie says while there is an ''adrenalin rush'' as the ''now-or-never'' event arrives, the planning is protracted, the commitment intense.
''It's great to travel, to work in different places, with different cultures. London is home to 200 different foreign communities who speak 300 languages on a daily basis. LOCOG reflects that.
''But the challenge for me is in the logistics, in bringing everyone together, in making incredibly complex mega-projects like this work,'' said Pirrie, one of only two Australians closely involved with the London bid.
Henry agrees. She compares the production of torch relays to what she imagines childbirth must be like. ''It's tough. There'll be peaks and troughs. Some days the wheels will fall off.
''But all being well, at the end people will say, 'wow, it's a miracle … it worked out just like you said it would'.''
What does Edwards enjoy most about his job? ''Being close to the athletes - they're what this is all about. The buzz of the city. The history of the place. Hey, Captain Cook studied at the naval college across from me.
''And, the excitement of having a start date and a finish date when you know you have to deliver.''
Like his compatriots, Edwards feels proud of Australia's contribution, but privileged to be working as an ''honorary Englishman'' at an event that remains predominantly English won and run.
Perhaps it was not always thus. One old-timer recalls that during preparations for the 2002 Manchester Commonwealth Games, Sydney veterans had to reduce their profile, avoid making comparisons.
''For a while use of the word 'Sydney' was actually banned. Instead, we had to refer to it as 'the Other Place', or 'South Manchester'.''
Not that age-old sporting rivalries are set aside entirely during the long campaign to produce the greatest Olympics ever. As Michael Pirrie says, ''You take the spirit and characteristics of your country with you.
''The golden boxing kangaroos with red boxing gloves are already starting to appear more visibly in pockets around the office as we get closer to the Games.''
Meanwhile, expats are giving thought to what's next.
Henry has always fancied visiting Carnival, in Rio, site of the 2016 games. Edwards wants to ''put back'' into his sport, though he concedes after all the excitement ''a nine-to-five would probably be too mundane''.
But as Pirrie says, ''at the moment our total focus is on next year.''