To marry someone in Vietnam, you have to prove that you are eligible to marry with the Embassy of Vietnam.  Documents needed include:

1) an application for marriage registration

2) affidavit of single status

3) certificate of no-marriage records issued by the state or county Vital Statistics Office

4) certificate of good mental health

5) biographical information sheet.

Please note that going to the doctor for a general check-up will not suffice for the certificate of good mental health, the information must be presented on a specific form.

If you have been in a previous marriage you must submit a copy of the divorce decree.