Mediation services arise in contexts where the notions of community cohesion, relationship integrity and social order are valued over their opposites (disorder, dissent, conflict etc). Yet it is not at all clear whether and how the mediation of conflict works to re-establish harmony or consensus. Indeed it is not at all clear that mediation is always effective or just. It has even been suggested that some conflicts (e.g. work-place, commercial and sexual assault) are either not resolved or not resolved justly by mediation. On the other hand, advocates maintain that mediation can bring resolution and repair to ongoing relationships, promote community harmony, and empower people to be self-determining in the construction and maintenance of their resolutions. Whether mediation is adjudged positively or not, all mediation is instantiated in, indeed performed through, talk. In this paper I examine mediations from an Australian mediation program, and use Conversation Analysis to expose the practical methods by which mediators achieve consensus between disputants. I then examine a case in which mediation has failed to produce the sought-after consensus, and explore one way of understanding the failure of mediation in that case.