I second that good advice from Transpac.

Most Westerners think the wai is a greeting, like a handshake or a kiss near the cheek is to Westerners.
Wrong.
The wai is acknowledgement of social status among Thais, based on class, age, wealth, occupation, and family relationship.
The lower status wais to those above:
The child to the parent.
The student to the teacher.
The nurse to the doctor.
The waitress to the customer.
Every Thai knows their place in the social hierarchy, and the wai confirms and acknowledges that.

As Westerners we don't have a place in Thai social hierarchy.
Waiing is simply not appropriate for us.

Most tourists who try it, get it wrong.
If you wai first, you are acknowledging your social inferiority to the other person.
If you return a wai, but at the wrong level, well, you just look foolish.

I never wai.
When Thais wai to me -- which happens many times every day -- I only smile and nod in return.

- Peter
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