How does leverage vary across different mediators? What influence does this variation have on mediation outcomes? Extant literature has equated mediation leverage with material power. Leverage, however, is context dependent and comprised of two dimensions: capability and credibility. Capability leverage is a function of economic resources and power, while credibility leverage derives influence from historical and cultural ties that bolster a mediator’s contextual knowledge of a conflict. I hypothesize that mediators with capability leverage are more likely to achieve short-term success, whereas mediators with credibility leverage generate more durable settlements. I quantitatively test the hypotheses using civil war mediation attempts from 1989 to 2006. I find that capability leverage does indeed contribute to the achievement of short-term success; credibility leverage, however, generates a more durable peace. The results demonstrate the importance of understanding mediation leverage as a context-dependent concept and highlight the potential long-term benefits of softer forms of mediation.