Going on training course what Thai visa do I need?

Q: I am a Singaporean national currently working for a company in the USA. My company has assigned me to attend a training course in Thailand for 6 weeks. Should I apply for visa, and where can I do that?

Yes, you would need to obtain a Non-immigrant B visa before coming to Thailand. You may apply for such visa at any Royal Thai Embassy in the USA. The basic requirements are recommendation letter from your company verifying your status and assignment. You would also have to prove your legal immigration and employment status in the US and that you would be able to re-enter the US without any problems.