1. The golden rule is to address the problem immediately. Most issues can be sorted out quickly and easily, normally by the offer of an alternative room or accommodation. What is more, if you don't give the organiser a chance to sort things out, it might affect any compensation claims you make in the future.
In cases where there is no rep based locally, or if you feel the rep is not taking you seriously, contact the tour operator's head office in the UK.
2. If the threat of a formal approach gets you nowhere, you will need to start to compile your case. The more evidence you have, the better, says Bob Atkinson, travel expert at Moneysupermarket.com.
"To make a successful claim, keep all relevant receipts as well as your tickets and write down as many details as possible at the time, so you don't forget any key facts," he says.
3. If your issue is not sorted while you are on holiday, you must submit your formal complaint within 28 days of getting home. This is vital if it is an Atol-backed tour operator as the code of conduct and subsequent booking conditions will allude to this. Send the complaint recorded or registered post to the tour operator or log it with your travel agent if you booked in a shop.
Your letter should clearly state the problem, a list of who you spoke to and when, plus any action that happened and compensation sought.
Take into account a proportion of the cost of the holiday to reflect the number of days spoilt by the problem; a sum to compensate for "loss of enjoyment"; and refunds for any reasonable extra expenses you incurred as a result.
Industry experts agree that very few claims for a full refund succeed, and it is fairly unusual to get back even half the cost. If you are unsure about how much financial redress to seek, talk to your local Citizens Advice Bureau.
4. It is crucial to keep copies of everything you send. Your letter should be acknowledged as received within one week and you should get a full first reply with one month from an Atol-backed tour operator. Otherwise, the wait may be longer – especially with airlines, which usually take more time to respond. If the problem was a flight delay, note that you are only due compensation if the flight was delayed by more than three hours.
5. If you are unhappy with your compensation, you can appeal to the company. In the meantime, do not bank any cheque that you are given as this will be regarded as accepting the offer.
6. If you are still unhappy - or after eight weeks of unsatisfactory correspondence - you can threaten to take your case to arbitration or to the Small Claims Court. If you have a good case, operators will often make a better offer at this point. If not, you have two main options: those with complaints against Abta members can use its arbitration and mediation service to obtain a final decision.
This will cost between £108 and £264 in fees. If the company is not an Abta member, your next recourse may be to take them to the Small Claims Court.This will allow you to claim up to £5,000 in England and Wales or £3,000 in Scotland or Northern Ireland. For details, visit justice.gov.uk.