This article is from the Mongolia FAQ, by Oliver Corff with numerous contributions by others.
Here as above it is recommended to contact your university or your
national academic exchange service. You are strongly discouraged to
go to Mongolia posing as a foreign language teacher if you are not one
for purposes other than teaching, e.g. missionary work. While in the
beginning of the 1990s it was still possible to do so, anyone not
being sent by an acknowledged academical institution or governmental
body must now show certificates proving his/her qualification as a
teacher.
In addition, every foreigner staying within Mongolia for more than a
month has to register with police. In case of foreign experts,
foreign personnel etc. the employer or host will certainly assist.
Not registering has consequences when leaving the country. Regularly
you get fined (anything near USD100.--) and you may risk missing your
plane/train. You may even appear with your nationality and name
spelled out in full in a newspaper article. Not registering is not
worth the trouble.
 
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