Tipping
Tipping has not been customary in Vietnam, but as the flow of tourists has increased in recent times, service charges and the expectation of a small tip has become more common in typical tourist places.
In a country where GNI (gross national income) per capita in 2002 was US$ 430 (less than NOK 3000 a year), a few thousand Dong is enormously appreciated. But there are however times when it can be taken the wrong way. At small hotels, the staff frequently goes out of their way to answer questions, reconfirm plane reservations, look up addresses and so on. This is a great honor and their way of saying they consider you a friend. But remember, friends don't tip friends. A tip, no matter how well intentioned may invariably be taken as an insult.
Your best bet in such situation is to buy small gifts for the staff, such as flowers, pastry, candy- things you would buy for a friend at home (try to avoid buying “typical Vietnamese tourist crafts” such as e.g. lacquer ware and pottery).