Rail freight crossing international borders

I'd like to know what the procedures are, going through customs, etc.

I'm particularly interested in what happens at the US/Mexico border, but I'd be happy to know about what goes on anywhere else for comparison.

Thanks.

Thats kinda private there dude. It would be stupid for any railroad employee to give that kinda information out to the public.

Feel free to PM me if you have any questions why i locked this topic.