"There's two big ones for the most part, the Romulans and the Klingons. We've got treaties with both to establish a Neutral Zone between their territory and ours, and in theory, we each stay on our own side of the border." In practice, not so much, naturally.

"They're both societies that do the whole... warrior honor code thing, though they're pretty different. The Klingons treat combat and conflict like it's some kind of religious experience - really ritualized, lots of emphasis on glory in battle, that sort of thing. The Romulans tend to be more diplomatic and politicized, and there's a lot more to do about loyalty and family honor than personal acclaim."