You can do a CELTA at Language Link. More info at www.languagelink.edu.vn I don't know when the next course is being offered, but you can contact them.

Yup. So far as I know Language Link's the only place offering a CELTA course up north, and I would definitely go with CELTA if your planning on teaching to adults for a little while. Its 4 weeks and the most intenste ESL certificate, but its well worth the value as you do learn a lot from the course and employers love it. If you have a lot of business experience you should apply to RMIT Vietnam. They are always looking for both people who can teach and have bus experience, and they have the best package of any school in Hanoi, barring perhaps the British Council. High salary, paid sick leave, paid annual leave, full health insurance etc. On the other hand they've got the longest hours.