I do not know the answer to your question, Hermanolobo. The TEFL course I conduct in Phuket is recognised and endorsed by the Thai Ministry of Education so the teaching institutions can always check with them as to the validity of the certificates we issue. We have regular inspections by members of the Phuket Educational Service Area Office who report directly to the Thai Ministry of Education. Our certificates are numbered and these are also recorded with the ministry. I know of a few other TEFL places that have the same thing so they should be able to be used overseas - although I have yet to meet anyone who has successfully done so. cheers, Whisper.