London's Heathrow Airport's immigration queues caused yet more travel nightmares this week, with non-European passengers waiting for over three hours.
So bring a book or make sure your electronic devices have enough charge to get you through the long wait.
UK Immigration boss Brian Moore told the BBC "the vast majority of passengers pass through immigration control quickly" -- a claim that'll be greeted with howls of laughter from anyone who's been stuck in Heathrow's queues for hours on end.
The reason for the chaos appears to be chronic understaffing and a rainy evening at Heathrow, which led to a few flight delays. Rain is not, needless to say, an especially unusual occurrence in London.
Business travellers will be looking with some suspicion at immigration chief Moore's insistence that the UK Borders people are "fully prepared to manage busy periods", particularly during the 2012 Olympics.
If you're heading to London this UK summer, don't miss our roundup of the days Heathrow is likely to be worst affected by overcrowding -- and what you can do about it.
Heathrow's worst immigration delays last week were at Terminal 5, home to most of Qantas partner British Airways' flights.
That's the newest, most advanced terminal in the otherwise dilapidated Heathrow. You'll fly through T5 if connecting to Red Roo, BA or oneworld partner flights, many of which leave from the older Terminal 3.
Terminal 5 is supposed to be the terminal least affected by queues at immigration, according to planning by the airport operator BAA.
Avoiding the queue? Your other options
If you're heading to the UK, smaller airports may offer less of a queue. While Qantas and its partner British Airways only serve Heathrow for flights from Australia, many European airlines have decent connections via their hubs to other UK cities.
So if you've still got time to change your plans, consider KLM via Amsterdam, Lufthansa via Munich or Frankfurt, Finnair via Helsinki, Brussels Airlines via Brussels, SAS' Scandinavian hubs or even Air France via Paris (usually an airport we avoid).
Some Asian and Middle East airlines also fly directly from their own hubs to UK regional airports. Emirates has flights to several UK cities, for example.
If you're bound via London for other European destinations, consider rerouting to avoid Heathrow. While most Qantas flights head for LHR, the Red Roo also has Singapore-Frankfurt flights.
Contact your airline -- even if your ticket carries change penalties -- and see whether there's extra flexibility in the circumstances.
And if you must head through Heathrow, check out the AusBT guide to London Heathrow for maps, guides, frequent flyer tips and business traveller tricks to navigating one of the world's most frustrating airports.