Many modern armed conflicts contain more than two fighting parties, or armed opposition groups that have factions within them. It is the moderates in an armed opposition that governments negotiate with. But the agreement's fate depends on the approval of all other significant actors within the opposition. We construct a dynamic model of conflict in which such an actor is to decide whether to accept a peace agreement signed by the moderates or not. Using this model we analyze the behavior of our decision maker, focusing on outcomes like the optimal settlement strategy, expected duration of the conflict, and the decision maker's expected payoff from conflict. We then determine how these outcomes are affected by changes in the conflict environment. Finally, we extend our model to analyze the implications of commitment problems, and the possibility that the conflict ends with military victory of either side.