Note: I'm writing about Alliances, NOT MPP's. I avoid MPPs unless there's absolutely no other way.
If a Civ declares war on me, or me on them, if at all possible, every other Civ in the game that I can get to ally with me, I do so. I usually time my war declarations (if I do it, rather then being declared ON) so that my lux I'm selling are up for renegotiation, and I have some cash around.
What happens then is: 20 turns later, I will probably cancel alliances and make peace, no rep hit. Of course, that's *if* the civ(s) I'm at war with still exist to make peace with. Then I watch the rest of the world at war for at least another 40 or so turns, while I peacefully build up and pick my next target, or work toward whatever type of victory I want/can get.
I *always* figure 20 turns of war if I bring allies in. Usually the AI's will cheat you by making peace early. Just remember, always go around and cancel the alliances that havent' already been cancelled by the AI by making peace before you make peace yourself, unless of course you're getting your butt kicked and have to make peace to survive. The only exception to 20 turns of war is if the civ(s) you allied against are eliminated. Then the alliance(s) are gone anyway. Can't ally against the Germans if they are wiped out, can you?

:rocket:
