“Reactive devaluation” is a cognitive bias that occurs when a proposal is devalued because it comes from an adversary. Applied to mediation, it is not uncommon for a party to reject a proposal made by the opposing party for no apparent reason other than it came from the opposing party. When the proposal is made by the mediator, however, reactive devaluation is significantly reduced. Thus, a party might agree to a proposal made by the mediator, even though it would not have agreed to that proposal if it had come from the opposing party.