Good, question. It depends some what by what you mean by trust and who. Do you mean strategies that apply across agent and/or person space or are things that rely on human specific psychology ok? Also, by trust do you mean reliably honest, reliable as an ally, or something else. I would be interested in all of those sub varieties, but which one is being addressed would be pretty important for any given article. Strategy of conflict is very good for how to ensure trust in a fairly unusual, but useful sense of the word.
I was thinking about which people you trust in important matters-- spouses or the equivalent, employees, employers, doctors, investments, that sort of thing. If you'd like a LessWrongian flavor, who would you trust to take care of your affairs while you're frozen, and why?
One of the more important types of decisions is deciding who to trust and about what, but I don't think I've seen any discussion here about rational methods in that area.
Any suggestions?