What to avoid
• Any negative comments about the country and King should be avoided. If you insult the country and the King, you will almost certainly stop any chance of building good relationships with the Thai and it could possibly even lead to legal action. You should make sure you treat all images of the royal family with respect.
• Any image of a Buddha should also be treated with extreme respect. Do not point the soles of your feet in the direction of a Buddha or touch or deface any image or statue of a Buddha or monk.
• In Thai Buddhism, the head is regarded as sacred. For example, passing items over someone's head can cause great offence. Similarly, the feet are considered dirty. The feet should not be used to point to things and should not be placed near any objects that are associated with the head.
• Do not pass anything with your left hand, and never point with one finger.
• It is common practice to remove shoes before entering a Thai home. Thai people are very conscious about cleanliness and wearing shoes inside is not appreciated.
General Etiquette
• Courtesy is very important to Thai people. Being polite and respectful to others is considered essential to maintaining good relationships. Speaking softly and smiling warmly will always help to create positive feelings.
• As in many other Asian countries, you should avoid angering or insulting someone (causing someone to “lose face”). Open criticisms and negative responses are seen as an insult to other people and can cause them to think disrespectfully of you. If you need to give a negative response, do so indirectly.
• Public displays of emotion are best avoided. It is considered inappropriate to show anger or a negative emotion.
• There is a strong hierarchy in Thai society which is evident at many levels. When Thai people meet someone for the first time, it is not unusual for them to ask several questions in order to establish where they fit within the hierarchy. These questions may seem very personal to some foreigners but it is best to accept them in good nature and don't be insulted.
Greetings
• Thai greetings often involve a wai. To wai, the hands are raised as if in prayer and the head is bowed.
• There are strict rules concerning who and how to wai. Generally, the younger person initiates the wai. The lower the head is bowed, the more respect is shown. As foreigners are usually not expected to know the wai etiquette, mistakes will be excused.
Business Etiquette
• Thai people prefer to build personal relationships before discussing business. Initial meetings will always take place over lunch or drinks and entertainment is part of developing business relationships. Thai people generally value enjoyment (kwam sanuk).
• Thai people laugh very easily and a foreigner can minimize his errors or embarrassment through laughter. If somebody starts laughing without any apparent reason, it is best to change the subject. He or she is probably embarrassed.
• A business card should be offered with the right hand. Take time to read the card and make a polite comment about it.