A worrying prospect

Student email, quoted in its entirety:

Hello Professor!

Okay....so I have been thinking a lot about a major and what I am going to do...

My question to you is, what would you title the people who go into, say, third world countries and teach the people there how to plant crops or irrigate the most efficiently or raise cattle...but more along the agricultural side. What would you call those people?

If I was the "the people" in "third world countries," I'd be scared.