Some UK airlines could face huge compensation bills from passengers following a European court ruling on flight delays.
A number of airlines, including British Airways and easyJet, had challenged a 2009 ruling that passengers on flights to and from Europe should be compensated if they are delayed for more than three hours.
However, the European Court of Justice (ECJ) in Luxembourg confirmed the 2009 ruling after the airlines had challenged the UK's Civil Aviation Authority (CAA) over the matter.
There will still be exceptional circumstances where compensation will not have to be paid, such as industrial action and extreme weather. But there are a number of compensation cases that have been put on hold since 2009 for which carriers might now have to pay out.
The judgment was welcomed by the CAA, which said the situation was now clearer for passengers.
CAA regulatory policy director Iain Osborne said: "Every year around 200 million passengers travel on two million flights to and from the UK, with the vast majority experiencing no problems. However, when something does go wrong, there are regulations in place to protect travellers and the CAA is ready to ensure companies abide by them.
"The judgment from the Court of Justice of the European Union offers much-needed clarity for passengers, the airline industry and the CAA about when compensation must be paid following delays."
A British Airways spokesman said: "We are aware of the ruling and will continue to comply with the regulations."
Travel company Tui, which was involved in the legal challenge, said: "We note today's ruling by the ECJ.
"We are committed to treating our customers fairly and will continue to work with the European institutions to ensure that the underlying legislation is revised such that it strikes the right balance for passengers and airlines."
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If you are a victim of a strike, or any other event beyond the airline's control (including ash clouds!), they must offer you a refund (in which case it's up to you to find a way home) or an alternative flight. While you are waiting for the flight you have the right to food and refreshment and accommodation.
If you are on a package holiday, your tour operator is entirely responsible for looking after you until you get back to the UK.
This is more likely to happen due to the financial crisis, but in some situations you are covered.
If you pay by credit card and it's over £100, you'll get a refund from the card company.
Your travel insurance may well cover you too, but check before you go.
Talk to the airline, and if it is temporarily misplaced they should arrange for it to be sent to your accommodation, and you should be either given cash to cover the essentials in the interim.
If it's completely lost you must wait 21 days and then make a claim for compensation. If you are travelling as part of a package you can claim costs from your operator.
If you are travelling within the EU you need an EHIC card, which gives you access to public healthcare. However, this won't necessarily be free, and if you need extra services such as accommodation for a carer, a helicopter home or a delayed flight, you could end up seriously out of pocket.
The only protection that will guarantee you will be looked after without running up a horrendous debt is by having travel insurance - which often covers up to £10 million of costs.
The most common form of theft is pick-pocketing, followed by theft from a car and bag snatching. Meanwhile, 752,000 of those surveyed had items stolen from their hotel room or villa.
If you have anything stolen, your only protection is insurance. You need to tell the local police immediately and get a crime reference for your travel insurer.