Have you been on a short-term mission trip?

Where did you go? How did it go? What were you glad you knew before leaving? What do you wish you knew before leaving?

I have been going on and leading short-term mission trips for more than 25 years. I was recently asked to put together a 3–4 week training on short-term mission trips for a church. It has caused me to really evaluate what information I take for granted as someone who has been traveling for so long, and I'd like to get some feedback that might help me craft my material.

In addition to what was already asked, perhaps you've never been on one, and you can provide some insight on what information you think would be helpful if you were considering it for the first time.