You're sitting in a hip Tokyo cafe, having a fish cake and sake. Your server has been especially attentive, so when the check arrives, you think nothing of pulling out some extra yen and leaving a healthy 20 percent tip. But suddenly things go horribly wrong: the server turns wide-eyed, becomes agitated, and walks away. What happened?!

Tipping in Japan [Images] and many other Asian countries is simply not a way of life. In fact, it's usually regarded as a vulgar display of wealth and a disregard for the culture. The same can be true in Europe and Latin America... though not always. And in the US of course, tipping is expected (and sometimes demanded). With expectations all over the map, it's not surprising that anxiety and confusion about whom to tip -- and how much -- are commonplace for travelers.

So we've done the legwork for you, talking with concierges, tourist boards, and other travelers to find out the real protocol on when (and when not) to reach into your wallet and how much of a tip you should give to waiters, sky caps, maids, doormen, and cabbies all over the world.

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Of course, tipping is confusing enough for Americans traveling domestically. The expectation is to tip not only big but also often, from the kid handing you a Venti coffee at Starbucks to the multiple hotel hands that rush to open doors, carry bags, and offer an escort to the hotel room.

Go abroad and the situation changes. The legion of skycaps, cab drivers, bellboys, and waiters may perform the same services as their US counterparts, but they often have radically different expectations of a tip. You can credit different customs, as well as a service industry with a different wage scale. In the US, tips usually abet low wages. In other parts of the world, service employees are often paid a living wage. If you're taking a taxi in Chile or New Zealand [Images], for example, the driver won't give you the evil eye if you don't tip -- it's not expected.

At a hotel, you'll encounter more people who potentially need to be tipped than anywhere else during your travels. In fact, there are so many people it can become confusing. If a doorman opens the door of your cab, another takes your bag, and a third delivers it to your room, who gets the tip? It should be the last person in the chain -- the one who actually brings the bags to your room. And at checkout, only tip the one who loads your bags onto a cart and takes them out of the room.

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Restaurants can be tricky, too: keep an eye out for the service charge. In many European countries, this charge averages 10 percent, but it's usually included in the price of a meal. If it is, then do as the European do, and leave a few extra coins or round up the bill -- in cash, even if you've paid for the meal with a credit card. And if you're heading to Fiji, Malaysia, or South Korea, be aware that no tip is required in restaurants.

The Tipping Point

Here are some other scenarios:

Spa Therapists: Tipping 15 or 20 percent is common practice in the United States but rare at any spa abroad, where a service charge is typically added to the cost of the treatment.

Concierges: Situational. If a concierge gets you theater or train tickets, or has been especially helpful during the course of your stay, then a $10 or $20 tip (in local currency) is in order.

Guides: Booking a ski guide to take you off-piste in Switzerland [Images], a golf pro in Scotland, or a fishing guide in Ireland? All should be compensated in the 10 to 15 percent range, as they would be in the US.

A good tip on tipping? Get small bills or coins from your hotel's front desk to make tipping easier. But if you have only large bills, it's perfectly acceptable to ask a hotel porter or even a skycap for change when you give them a tip. After all, tips are a part of their business. They're not embarrassed, and you needn't be either. And if you don't have local currency, US greenbacks can work just as well as a 'thank you' in London [Images], Lombok, or Lahore [Images].

• Slideshow: Guide to Tipping for Travelers

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