How to complain (like its mirror image, how to express appreciation) is a crucial social skill. Get it right through what you might call ‘constructive complaining’ and you can expect service beyond the call of duty — at least the next time.

The best thing that can happen to you with an airline or a hotel is to have some kind of problem: that gives you the excuse to build a relationship with the folks in the front line. This is the fast track to surprise upgrades and a better class of junk mail. If you have a complaint, complaints experts in the travel trade want to hear from you. (Whether they’ll listen is another matter.) The axiom is that of all people who have a reason to complain only one third do. And they each will tell 10 more people about their problem. But people whose complaints are answered will be more loyal than those who have never had a problem.

People respond to ‘problems’ depending on their mood (or mode) or how crucial the consequences. Flying back from a successful meeting, I’m going to be fairly relaxed at the prospect of a two-hour delay at Shanghai, whereas the same glitch on the way out might send me ballistic. Many problems should never become ‘complaints.’ (And vice versa.) Most can be solved on the spot with a modicum of grace and complicity. ‘Could you ask the pilot to tweak up the air conditioning?’ Or ‘Do you have a quieter room?’ Sending back a steak or a corked bottle of wine is an art form that can deliver dividends.

But for serious complaints — flight cancellations, lost luggage, over-charging, or hours spent stranded on an airport runway without food or drink — it is often tough and time-consuming to get redress. But only be as tough as you need to be. Most diplomats agree that a gradual step-by-step escalation of protest gets the best results. When you want to complain about a service or the treatment you have received, give the other party a chance to resolve the problem. Customer service representatives can often sort things out on the spot — especially if you get them on your side, and help them to save face. Always expect the unexpected. Pre-empt problems by asking what market research people call ‘forced choice’ questions when you call reservations. Don’t say: ‘Hi, I’m John Doe, just to confirm that I’m on the flight from New York to Hong Kong.’ Do say: ‘I’m John Doe; which flight am I booked on out of New York?’ Ask for names and note the time of your call. Read the small print of rules and conditions — especially discounted airline tickets.

Know your rights on matters like denied boarding compensation, flight cancellation, lost luggage. There are consumer protection laws to protect travelers against unfair contract terms and misleading descriptions. Check your insurance policy.

Try to sort out problems on the spot in a low-key manner with the minimum of hassle. Be polite but firm. Don’t over react over trifles. Match your demeanor with the size of the problem. Note the names of employees who were rude or especially helpful. Reserve your rights. Refuse to sign any disclaimer attached to payment of on-the-spot compensation.

Keep a diary of events, noting all phone calls and meetings and any response made — along with any offers of on-the-spot recompense such as drinks, meals or overnight accommodation. Take photographs. Video cameras are useful for recording noise and remarks (including your own!). Keep all your travel documents (ticket receipts, baggage-check stubs, boarding passes, etc.) as well as receipts for any out-of pocket expenses that you may have incurred as a result of the incident.

Complain as soon as possible. If you don’t, you’ve deprived the travel supplier of a chance to put things right — and so, in legal talk, you’ve ‘failed to mitigate your loss.’ This may affect the amount of compensation you get, whether by negotiation or from court action.

Don’t complain to ‘Customer Care’ or ‘The President.’ Seek out the name of a senior person.

Be calm and stick to facts. Don’t exaggerate what happened or clutter your complaint with petty gripes that obscure what you’re really angry about. Inform them about any special inconvenience, monetary loss, loss of business due to a dislocated schedule, or loss of enjoyment for a spoiled vacation. Say what you expect them to do to make amends. What would be a fair outcome in your mind?

Give a deadline for them to get back to you.

Cold logic is likely to get a better response than hot anger.

It never hurts to sleep on a complaint before you fire it off. (As William Wordsworth might have said, Vehemence is anger recollected in tranquility.)

[aside headline="" alignment="alignright" width="half" headline_size="default"]ROGER COLLIS Editor, TruthInTravel.com His columns, The Frequent Traveler (now in its 19th year) and Ask Roger Collis, every Friday in the International Herald Tribune have brought him worldwide recognition as a guru on business and leisure travel.[/aside]

Be reasonable: If your demands are way out of line your complaint could earn a polite apology and a place in the cranks file.

Persistence pays. Travel firms will offer the minimum recompense that they think you might accept.

Don’t be pressured into accepting vouchers or a discount on a future trip — better to hold out for cash.