How the partners in an alliance view their joint venture can have much to do with its success or failure. Do they fear that the other partner will get a larger payoff, while they operate in good faith? Or do they make seemingly counterintuitive unilateral commitments that involve acts of faith by one or both companies? Here the authors present a framework, derived from field interviews and viewed in game theory terms, for securing partners’ cooperation, managing an alliance, and ensuring its success.