Cambodia is a very conservative country where modesty is the order of the day. You can dress skimpily, but it won't do you any favors in terms of the Khmers' perception of you. Likewise, openly public displays of affection will embarrass people, so don't do it.
As with other countries in the region the concept of "face" governs social interaction on every level. You will get things done faster if you go out of your way to make sure that you don't cause someone to lose face. If you get angry, try not to show it. Another thing to remember is that a Cambodian reaction to uncertainty or embarrassment is to giggle or laugh. So if you ask a moto-taxi driver to take you to a destination and it turns out he has absolutely no idea where he is going and giggles when you point it out, don't get angry. He is not laughing at you; it's just the Cambodian way of diffusing tension.
Smile and joke as much as you can. It's the Cambodian way and people will be more willing to help you.
When you beckon someone, don't do it the Western way. Flap your whole hand downward with your palm flat. If you do it with your hand or finger pointing up, it is interpreted as either very rude or as a sexual gesture.
As in all Buddhist countries, the head is considered holy while the feet are considered dirty. Don't go around touching people's heads, even if it's just patting a child on the head. Likewise, don't point the soles of your feet at anyone and certainly not at a Buddha image. Cambodians tend to sit on the floor with their feet tucked to the side. Don't step over someone and don't step over food. It's considered very rude.
If you are in a temple, dress modestly. Have respect for monks in general. Women should never touch them.
The Krama: A Scarf for All Seasons
Everywhere you go in the Cambodian countryside, you will see the checkered pattern of the krama. This ubiquitous cotton scarf performs many functions. It shades a weary head from the sun. It keeps dust out of the eyes and mouth. It is a carryall, whether that be fruit, money, or babies. It is a skirt, a sarong, a tablecloth, a towel, and a hammock. I have even seen them used to temporarily fix the loose undercarriage of an aging Toyota Camry.
The krama is also, to some extent, the symbol of being Khmer and being a farmer. When Prime Minister Hun Sen (no privileged kid he, Hun Sun is from tough peasant stock in Kompong Cham Province) canvasses in the countryside he dons a krama, puts on the khaki cargo pants, and stands in rice paddies, reminding his constituents that he is the same as them.
There have also been very sinister uses of the krama in Khmer history. In 1978, Pol Pot ordered the Eastern Zone purged. The people of the east were transported to the "loyal" Southwestern Zone run by Pol Pot's brutal one-eyed henchman, Ta Mok. Each deportee was issued with a brand-new blue krama. Maybe they thought he was looking out for their physical well-being. In reality, Ta Mok ordered that anyone seen wearing the blue krama be marked for death.
Kramas do not come only in rough, practical cotton. There are also patterned silk versions with intricate stripes and patterns. The origins of the krama most likely lie in ancient Angkorian times when a simple cloth was used to cover the upper body. Variations of the krama are also worn by rural people in Laos and Thailand, but only in Cambodia is this simple piece of cloth an affirmation of identity.
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